PMID-sentid Pub_year Sent_text comp_official_name comp_offsetprotein_name organism prot_offset 21093571-5 2011 MATERIALS AND METHODS: S-mephenytoin, the CYP2C19 substrate probe, was incubated in the presence or absence of AP, CA and OS components. Mephenytoin 23-36 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 42-49 21325430-0 2011 Evaluation of the effects of 20 nonsynonymous single nucleotide polymorphisms of CYP2C19 on S-mephenytoin 4"-hydroxylation and omeprazole 5"-hydroxylation. Mephenytoin 92-105 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 81-88 21325430-6 2011 The activity of the CYP2C19 variants was investigated using two substrates, S-mephenytoin and omeprazole, and six different kinetic parameters were measured. Mephenytoin 78-89 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 20-27 19661214-0 2009 Identification of new CYP2C19 variants exhibiting decreased enzyme activity in the metabolism of S-mephenytoin and omeprazole. Mephenytoin 97-110 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 22-29 20877236-5 2010 Eupatilin and jaceosidin were also found to moderately inhibit CYP2C19-catalyzed [S]-mephenytoin 4"-hydroxylation, CYP2D6-catalyzed bufuralol 1"-hydroxylation, and CYP2C8-catalyzed amodiaquine N-deethylation. Mephenytoin 81-96 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 63-70 18654768-2 2008 The CYP2C19*17 allele has been associated with higher levels of CYP2C19 gene transcription and increased rates of omeprazole and mephenytoin metabolism. Mephenytoin 129-140 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 4-11 18071681-0 2008 Assessment of urinary mephenytoin metrics to phenotype for CYP2C19 and CYP2B6 activity. Mephenytoin 22-33 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 59-66 18294333-2 2008 The CYP2C19*17 allele had been associated with a two- and fourfold decrease in omeprazole and S/R-mephenytoin metabolic ratios. Mephenytoin 98-109 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 4-11 18071681-1 2008 OBJECTIVES: (S)-Mephenytoin is selectively metabolised to (S)-4"-hydroxymephenytoin by CYP2C19. Mephenytoin 12-27 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 87-94 18071681-8 2008 RESULTS: Cumulative excretion of 4"-hydroxymephenytoin in urine with beta-glucuronidase treatment collected from before mephenytoin administration up to 12-16 h thereafter showed the greatest difference between CYP2C19 genotypes and the lowest intra-individual variability (7%). Mephenytoin 43-54 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 211-218 17600081-2 2007 The new assay, which does not require high-performance liquid chromatography (HPLC) separation or mass spectrometric detection, is based on the release of tritium as tritiated water that occurs upon CYP2C19-mediated 4"-hydroxylation of (S)-mephenytoin labeled with tritium in the 4" position. Mephenytoin 236-251 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 199-206 17600081-8 2007 This assay represents a non-HPLC, high-throughput version of the classic (S)-mephenytoin 4"-hydroxylation assay, which is the most widely used method to assess the potential for CYP2C19 inhibition of new chemical entities. Mephenytoin 73-88 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 178-185 16922812-2 2006 The effects of four individual ginsenosides (Rb1, Rb2, Rc and Rd), two ginkgolides (A and B) and one flavonoid (quercetin) on CYP2C19-dependent S-mephenytoin 4 cent-hydroxylation and CYP2D6-mediated bufuralol 1 cent-hydroxylation were evaluated in human liver microsomes. Mephenytoin 144-157 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 126-133 17521300-6 2007 The S-4"-hydroxymephenytoin/S-mephenytoin ratio (CYP2C19) was increased on day 5 by artemisinin [1.69 (1.47-1.94)] and arteether [1.33 (1.15-1.55)] compared with day -6. Mephenytoin 28-41 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 49-56 17614006-4 2007 CYP2C19 showed a Michaelis-Menten pattern for midazolam 1"-hydroxylation and was inhibited by (+)-N-3-benzylnirvanol and S-mephenytoin, which are a standard potent inhibitor and a substrate of CYP2C19, respectively. Mephenytoin 121-134 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 0-7 17614006-4 2007 CYP2C19 showed a Michaelis-Menten pattern for midazolam 1"-hydroxylation and was inhibited by (+)-N-3-benzylnirvanol and S-mephenytoin, which are a standard potent inhibitor and a substrate of CYP2C19, respectively. Mephenytoin 121-134 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 193-200 17375979-6 2007 In the case of mephenytoin, defects in its metabolism may be attributable to >10 mutated alleles (designated as *2, *3 and others) of the gene expressing CYP2C19. Mephenytoin 15-26 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 157-164 16922812-4 2006 Increasing concentrations of each test compound were added to microsomal incubation mixtures containing a well-characterized marker substrate (S-mephenytoin for CYP2C19 or bufuralol for CYP2D6) to determine their IC(50) values (compound concentration yielding 50% inhibition of a marker enzyme activity), which were estimated by graphical inspection. Mephenytoin 143-156 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 161-168 16719381-1 2006 A reverse-phase, high-performance liquid chromatography method is described for the quantification of 4"-hydroxymephenytoin formed enzymatically from 14C-labeled (S)-mephenytoin following incubation with cDNA-expressed CYP2C19 or human liver microsomes. Mephenytoin 162-177 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 219-226 16679385-7 2006 Fluoxetine also inhibited CYP2C19-dependent S-mephenytoin 4"-hydroxylation in a time- and concentration-dependent manner in hepatocytes, HLMs, and recombinant CYP2C19 (KI 0.4 microM and kinact 0.5 min(-1)). Mephenytoin 46-57 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 26-33 16679385-7 2006 Fluoxetine also inhibited CYP2C19-dependent S-mephenytoin 4"-hydroxylation in a time- and concentration-dependent manner in hepatocytes, HLMs, and recombinant CYP2C19 (KI 0.4 microM and kinact 0.5 min(-1)). Mephenytoin 46-57 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 159-166 16751594-6 2006 In addition, CYP2C43 showed activity for (S)-mephenytoin 4"-hydroxylation, a marker reaction for CYP2C19. Mephenytoin 41-56 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 97-104 16307177-1 2006 CYP2C19 is a clinically important enzyme involved in the metabolism of therapeutic drugs such as (S)-mephenytoin, omeprazole, proguanil, and diazepam. Mephenytoin 97-112 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 0-7 15788366-3 2005 Of the P450 forms tested, CYP2C19-catalysed S-mephenytoin 4"-hydroxylation was extensively inhibited by both the lansoprazole and omeprazole enantiomers in a competitive and stereoselective manner; the S-enantiomers of both drugs inhibited the hydroxylation more than the R-enantiomers. Mephenytoin 44-57 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 26-33 15486075-7 2005 This behavior of CYP2C19 was also observed with S-mephenytoin as the substrate. Mephenytoin 48-61 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 17-24 15788366-4 2005 The estimated K(i) values determined for CYP2C19-catalysed S-mephenytoin 4"-hydroxylation were 0.6, 6.1, 3.4 and 5.7 microM for S-lansoprazole, R-lansoprazole, S-omeprazole and R-omeprazole, respectively. Mephenytoin 59-72 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 41-48 15043991-3 2004 UA competitively inhibited CYP2C19-catalyzed S-mephenytoin 4"-hydroxylation with an IC50 (Ki) value of 119.7 (80.3) microM. Mephenytoin 45-58 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 27-34 15304427-10 2004 Aprepitant was a very weak inhibitor of CYP2C9 and CYP2C19, with Ki values of 108 and 66 microM for the 7-hydroxylation of warfarin and the 4"-hydroxylation of S-mephenytoin, respectively. Mephenytoin 160-173 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 51-58 15155554-7 2004 In addition to CYP2B6, ticlopidine also inhibited both mephenytoin 4-hydroxylation (CYP2C19) (IC(50), 2.7 microM) and dextromethorphan O-demethylation (CYP2D6) (IC(50), 4.4 microM). Mephenytoin 55-66 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 84-91 15145964-5 2004 All subjects took a 300-mg St. John"s wort tablet or placebo three times daily for 14 days, and then the activities of CYP2C19 and CYP1A2 were measured using mephenytoin and caffeine. Mephenytoin 158-169 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 119-126 12919185-2 2003 METHODS: CYP2C19 and CYP2D6 activities were assessed using the probe drugs mephenytoin and debrisoquine, respectively. Mephenytoin 75-86 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 9-16 15499174-1 2004 Metabolic capacities for debrisoquin, sparteine, mephenytoin, nifedipine, and midazolam, which are substrates of polymorphic CYP2D6, CYP2C19, and CYP3A, have been reported to exhibit, in many cases, remarkable interindividual and ethnic differences. Mephenytoin 49-60 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 133-140 12900870-4 2003 Using a chiral micellar electrokinetic capillary chromatography assay, the aromatic hydroxylation of MEPH catalyzed by CYP2C19 could thereby be confirmed to be highly stereoselective, an aspect that is in agreement with data obtained via urinary analysis after intake of racemic MEPH by extensive metabolizer phenotypes. Mephenytoin 101-105 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 119-126 12900870-2 2003 Mephenytoin (MEPH), dextromethorphan, diclofenac, caffeine, and methadone (MET) were successfully applied as test substrates for CYP2C19, CYP2D6*1, CYP2C9*1, CYP1A2, and CYP3A4, respectively. Mephenytoin 0-11 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 129-136 12900870-2 2003 Mephenytoin (MEPH), dextromethorphan, diclofenac, caffeine, and methadone (MET) were successfully applied as test substrates for CYP2C19, CYP2D6*1, CYP2C9*1, CYP1A2, and CYP3A4, respectively. Mephenytoin 13-17 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 129-136 12900870-4 2003 Using a chiral micellar electrokinetic capillary chromatography assay, the aromatic hydroxylation of MEPH catalyzed by CYP2C19 could thereby be confirmed to be highly stereoselective, an aspect that is in agreement with data obtained via urinary analysis after intake of racemic MEPH by extensive metabolizer phenotypes. Mephenytoin 279-283 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 119-126 12835613-2 2003 Most studies on carisoprodol metabolism have been carried out on individuals phenotyped for CYP2C19 activity using the probe drug S-mephenytoin. Mephenytoin 130-143 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 92-99 12869636-1 2003 CYP2C19 is an important human drug-metabolizing enzyme that metabolizes a number of clinically used drugs including the antiulcer drug omeprazole, the anxiolytic drug diazepam, the beta-blocker propranolol, the antimalarial drug proguanil, certain antidepressants and barbiturates, and the prototype substrate S-mephenytoin. Mephenytoin 310-323 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 0-7 12844133-8 2003 The area under the concentration-time curve ratio of S-nirvanol/S-mephenytoin, an index of CYP2B6 activity, increased 1.9-fold (P <.05) in CYP2C19 poor metabolizers during artemisinin multiple-dose administration, whereas the urinary excretion ratio of hydroxytolbutamide plus carboxytolbutamide/tolbutamide remained constant during the study period. Mephenytoin 64-77 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 142-149 12695344-6 2003 In vivo inhibition constants (K(i)iv) were obtained from a study of the disposition of a single oral dose (100 mg) of the CYP2C19 probe (S)-mephenytoin in 12 healthy volunteers receiving fluvoxamine at 0, 37.5, 62.6, and 87.5 mg/day to steady state. Mephenytoin 136-151 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 122-129 12637241-7 2003 The rate of 4"-hydroxylation of S-mephenytoin, catalysed in humans by CYP2C19, was also low in dog liver (4.6 +/-1.5 pmol mg(-1) protein min(-1)) compared with human liver. Mephenytoin 32-45 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 70-77 12597994-1 2003 The effects of serum proteins on the in vitro hydroxylation pathways of mephenytoin (CYP2C19) and debrisoquine (CYP2D6) were studied to enhance the predictability of in vivo drug metabolism from in vitro assays. Mephenytoin 72-83 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 85-92 12637241-18 2003 Correlation analysis suggested that CYP2B11 catalyses the N-demethylation of dextromethorphan (mediated in humans by CYP3A) and the 4"-hydroxylation of mephenytoin (mediated in humans by CYP2C19) in the dog, and that this enzyme and CYP3A12 contribute to S-warfarin 7-hydroxylation (mediated in humans by CYP2C9). Mephenytoin 152-163 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 187-194 12450547-6 2003 This method is well suited for the phenotypic evaluation of CYP2C19 activity using mephenytoin. Mephenytoin 83-94 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 60-67 12228186-7 2002 The tertiary amine TCAs, amitriptyline and imipramine, also inhibited CYP2C19-catalyzed S-mephenytoin 4"-hydroxylation (estimated K(i) of 37.7 and 56.8 micro M, respectively). Mephenytoin 88-101 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 70-77 12464799-1 2002 CYP2C19 is a clinically important enzyme responsible for the metabolism of a number of therapeutic drugs, such as mephenytoin, omeprazole, diazepam, proguanil, propranolol and certain antidepressants. Mephenytoin 114-125 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 0-7 12464799-7 2002 CYP2C19*10 exhibited a dramatically higher K(m) and lower V(max) for mephenytoin. Mephenytoin 69-80 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 0-7 12124312-3 2002 The activities of the CYP2C19(H99I) mutant and the chimeras that replaced residues 228-340 were lower than those for CYP2C19 toward S-mephenytoin, aminopyrine, and testosterone. Mephenytoin 132-145 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 22-29 12124312-3 2002 The activities of the CYP2C19(H99I) mutant and the chimeras that replaced residues 228-340 were lower than those for CYP2C19 toward S-mephenytoin, aminopyrine, and testosterone. Mephenytoin 132-145 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 117-124 11422005-0 2001 Mephenytoin as a probe for CYP2C19 phenotyping:effect of sample storage, intra-individual reproducibility and occurrence of adverse events. Mephenytoin 0-11 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 27-34 15618670-7 2002 Selegiline inhibited CYP2B6-mediated (S)-mephenytoin N-demethylation activity and CYP2C19-mediated (S)-mephenytoin 4"-hydroxylation activity. Mephenytoin 99-114 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 82-89 12060642-7 2002 Incubations with S-mephenytoin and omeprazole, substrates of CYP2C19, inhibited metabolism by human liver microsomes, supporting the involvement of CYP2C19. Mephenytoin 17-30 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 61-68 12060642-7 2002 Incubations with S-mephenytoin and omeprazole, substrates of CYP2C19, inhibited metabolism by human liver microsomes, supporting the involvement of CYP2C19. Mephenytoin 17-30 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 148-155 12019193-7 2002 S-Mephenytoin, a selective CYP2C19 inhibitor, inhibited 18-MC O-demethylation by 65% at a concentration of 2 times its K(I), and antibodies against rat 2C (human CYP2C8, 2C9, 2C19) inhibited 18-HC formation by 70%. Mephenytoin 0-13 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 27-34 11907490-6 2002 Moreover, the S/R ratio of mephenytoin showed a small but significant increase (median difference, 0.02; 95% CI, 0 to 0.31; versus 0; 95% CI, -0.01 to 0.06), indicating an inhibition of CYP2C19. Mephenytoin 27-38 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 186-193 11694260-4 2001 CYP2C19 genotype is a major determined factor for metabolisms of S-mephenytoin (S-MP), diazepam, and omeprazole (OP). Mephenytoin 65-78 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 0-7 11694260-4 2001 CYP2C19 genotype is a major determined factor for metabolisms of S-mephenytoin (S-MP), diazepam, and omeprazole (OP). Mephenytoin 80-84 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 0-7 11422005-1 2001 AIMS: To further evaluate mephenytoin as a probe for CYP2C19 phenotyping. Mephenytoin 26-37 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 53-60 11422005-10 2001 Our data support the use of mephenytoin as a safe drug for CYP2C19 phenotyping. Mephenytoin 28-39 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 59-66 11294510-0 2001 P-hydroxylation of phenobarbital: relationship to (S)-mephenytoin hydroxylation (CYP2C19) polymorphism. Mephenytoin 50-65 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 81-88 11270912-4 2001 Mephenytoin was used to assess CYP2C19 activity before and after 6 weeks and 12 weeks of fluoxetine. Mephenytoin 0-11 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 31-38 11259331-4 2001 Desmethylflunitrazepam formation was inhibited 31% by S-mephenytoin and 78% by ketoconazole, suggesting involvement of both CYP2C19 and CYP3A4. Mephenytoin 54-67 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 124-131 11124228-9 2001 Delavirdine significantly inhibited cDNA-expressed CYP2C19-catalyzed (S)-mephenytoin 4"-hydroxylation in a noncompetitive manner, with an apparent K(i) of 24+/-3 microM. Mephenytoin 69-84 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 51-58 11329260-0 2001 Identification of human CYP2C19 residues that confer S-mephenytoin 4"-hydroxylation activity to CYP2C9. Mephenytoin 53-66 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 24-31 11329260-1 2001 CYP2C19 is selective for the 4"-hydroxylation of S-mephenytoin while the highly similar CYP2C9 has little activity toward this substrate. Mephenytoin 49-62 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 0-7 11329260-2 2001 To identify critical amino acids determining the specificity of human CYP2C19 for S-mephenytoin 4"-hydroxylation, we constructed chimeras by replacing portions of CYP2C9 containing various proposed substrate recognition sites (SRSs) with those of CYP2C19 and mutating individual residues by site-directed mutagenesis. Mephenytoin 82-95 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 70-77 11329260-3 2001 Only a chimera containing regions encompassing SRSs 1--4 was active (30% of wild-type CYP2C19), indicating that multiple regions are necessary to confer specificity for S-mephenytoin. Mephenytoin 169-182 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 86-93 11180294-0 2001 Phenotype analysis of cytochrome P450 2C19 in Chinese subjects with mephenytoin S/R enantiomeric ratio in urine measured by chiral GC. Mephenytoin 68-79 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 22-42 11395323-6 2000 The limit of detection was less than 5 ng/ml, and the method was applied to extracts of human liver microsomes, which had been incubated with S-mephenytoin [a probe substrate for cytochrome P450 (CYP) 2C19]. Mephenytoin 142-155 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 179-205 11334262-3 2001 Both cimetidine and omeprazole inhibited each of the CYP subfamily enzymes; in particular, omeprazole extensively inhibited the hydroxylation of S-mephenytoin (CYP2C19, Ki = 7.1 microM). Mephenytoin 145-158 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 160-167 10976546-3 2000 OBJECTIVE: We sought to assess the effect of sex and intake of oral contraceptives on CYP2C19 activity as measured by the probe drugs mephenytoin and omeprazole. Mephenytoin 134-145 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 86-93 11034254-3 2000 Dextromethorphan was used as the probe for CYP2D6 activity and mephenytoin was used for CYP2C19 activity. Mephenytoin 63-74 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 88-95 10955816-9 2000 Although sulfaphenazole (an inhibitor of CYP2C9) and S-mephenytoin (an inhibitor of CYP2C19) partially inhibited the disappearance of MPA, no effect of the anti-CYP2C antibody was observed. Mephenytoin 53-66 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 84-91 10976550-1 2000 BACKGROUND: We have previously found decreased CYP2C19 activity in Tanzanians tested with mephenytoin and omeprazole in relation to genotype when compared with white and Asian subjects. Mephenytoin 90-101 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 47-54 10901692-7 2000 In contrast, S-mephenytoin inhibited DDS-NHY by CYP2C9, CYP2C18, and CYP2C19 by 27 +/- 2, 49 +/- 1, and 32 +/- 4%, respectively. Mephenytoin 13-26 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 69-76 10862503-8 2000 In studies with CYP-specific model activities, both selegiline and desmethylselegiline inhibited the CYP2C19-mediated S-mephenytoin 4"-hydroxylation with average IC50 values of 21 microM and 26 microM, respectively. Mephenytoin 118-131 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 101-108 10774624-16 2000 Further, in special populations, such as in elderly patients, poor metabolizers of sparteine (CYP2D6) or mephenytoin (CYP2C19), and patients with liver impairment, the measurement of plasma concentrations may be useful. Mephenytoin 105-116 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 118-125 10784435-6 2000 Additionally, we investigated the inhibitory effect of bisphenol A on CYP2C19-mediated S-mephenytoin 4-hydroxylation. Mephenytoin 87-100 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 70-77 10774635-6 2000 CYP2C19, but not CYP2D6, appears to be involved in the demethylation pathway, with a stereoselectivity toward the (D)-enantiomer of TRI, as a significant positive correlation was calculated between the mephenytoin (S)/(R) ratios and the concentrations to dose-to-weight ratios of (D)-TRI (r = 0.69, p = 0.00006). Mephenytoin 202-213 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 0-7 11343579-1 2000 In an open trial 11 in-patients with a major depressive episode (ICD-10), extensive metabolizers of mephenytoin (CYP2C19) and dextromethorphan (CYP2D6) and who were non-responders to a 3-wk pretreatment with 40 mg/d citalopram (Cit), were co-medicated for 7 wk (days 0-49) with fluoxetine (Fluox) (10 mg/d). Mephenytoin 100-111 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 113-120 10714950-3 2000 S-Mephenytoin hydroxylation genetic polymorphism is due to two mutations of the CYP2C19 gene, namely CYP2C19*2, located in exon 5, and CYP2C19*3, located in exon 4. Mephenytoin 0-13 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 80-87 10714950-3 2000 S-Mephenytoin hydroxylation genetic polymorphism is due to two mutations of the CYP2C19 gene, namely CYP2C19*2, located in exon 5, and CYP2C19*3, located in exon 4. Mephenytoin 0-13 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 101-108 10714950-3 2000 S-Mephenytoin hydroxylation genetic polymorphism is due to two mutations of the CYP2C19 gene, namely CYP2C19*2, located in exon 5, and CYP2C19*3, located in exon 4. Mephenytoin 0-13 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 101-108 10073749-4 1999 The CYP2C19 wild type (wt) gene and four mutant alleles associated with the poor metaboliser phenotype of (S)-mephenytoin, CYP2C19*2 in exon 5, CYP2C19*3 in exon 4, CYP2C19m4 in exon 9, and CYP2C19m3 in the initial codon were analysed. Mephenytoin 106-121 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 4-11 10647906-4 1999 Methylenedioxyphenyl compounds which possess a bulky structure such as 1,4-benzothiazine showed substantial inhibition of S-warfarin 7-hydroxylation catalysed by CYP2C9, S-mephenytoin 4"-hydroxylation by CYP2C19, bufuralol 1"-hydroxylation by CYP2D6, and testosterone 6beta-hydroxylation by CYP3A4. Mephenytoin 170-183 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 204-211 10510152-2 1999 The aim of this study was to determine the frequency of the defective alleles in CYP2D6 and CYP2C19 in Africans and to test whether the genotype for CYP2C19 is better correlated with the proguanil/cylcoguanil ratio than the mephenytoin S/R ratio. Mephenytoin 224-235 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 149-156 10460802-5 1999 Using S-mephenytoin as an inhibitor, the K(i) for inhibition of recombinant CYP2C19-mediated bufuralol hydroxylation was 42 microM, which is the approximate K(m) for recombinant CYP2C19-mediated S-mephenytoin metabolism. Mephenytoin 6-19 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 76-83 10460802-5 1999 Using S-mephenytoin as an inhibitor, the K(i) for inhibition of recombinant CYP2C19-mediated bufuralol hydroxylation was 42 microM, which is the approximate K(m) for recombinant CYP2C19-mediated S-mephenytoin metabolism. Mephenytoin 6-19 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 178-185 10460802-5 1999 Using S-mephenytoin as an inhibitor, the K(i) for inhibition of recombinant CYP2C19-mediated bufuralol hydroxylation was 42 microM, which is the approximate K(m) for recombinant CYP2C19-mediated S-mephenytoin metabolism. Mephenytoin 195-208 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 76-83 10460802-5 1999 Using S-mephenytoin as an inhibitor, the K(i) for inhibition of recombinant CYP2C19-mediated bufuralol hydroxylation was 42 microM, which is the approximate K(m) for recombinant CYP2C19-mediated S-mephenytoin metabolism. Mephenytoin 195-208 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 178-185 10411572-0 1999 A novel transversion in the intron 5 donor splice junction of CYP2C19 and a sequence polymorphism in exon 3 contribute to the poor metabolizer phenotype for the anticonvulsant drug S-mephenytoin. Mephenytoin 181-194 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 62-69 10411572-1 1999 Cytochrome P-450 (CYP) 2C19 is responsible for the metabolism of a number of therapeutic agents such as S-mephenytoin, omeprazole, proguanil, certain barbiturates, diazepam, propranolol, citalopram and imipramine. Mephenytoin 104-117 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 0-27 10379632-16 1999 Oral contraceptive (OC) use significantly decreased the CYP2C19 activity by 68% for mephenytoin as compared to non-OC using females. Mephenytoin 84-95 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 56-63 10379632-19 1999 For mephenytoin, the acidification procedure has been shown to be very important for the confirmation of CYP2C19 PMs. Mephenytoin 4-15 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 105-112 10096259-6 1999 RESULTS: Deficient mephenytoin hydroxylation was found in 4 subjects (2.9%; 95% confidence interval [CI], 0.1% to 5.7%) who were homozygous for CYP2C19*2. Mephenytoin 19-30 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 144-151 20654527-5 1999 The functionality of each expressed CYP2C was assessed by determining specific catalytic activities in these cells, that is, taxol-6-hydroxylation for CYP2C8; diclofenac-4"-hydroxylation for CYP2C9; S-mephenytoin-4"-hydroxylation for CYP2C18; S-mephenytoin-4"-hydroxylation for CYP2C19. Mephenytoin 201-212 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 36-41 9732415-0 1998 Identification of new human CYP2C19 alleles (CYP2C19*6 and CYP2C19*2B) in a Caucasian poor metabolizer of mephenytoin. Mephenytoin 106-117 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 28-35 10437143-1 1998 AIM: To improve HPLC method for rapid determination of urinary S/R-ratio of mephenytoin, a widely used metabolic index for cytochrome P-450 2C19 (CYP2C19) activity. Mephenytoin 76-87 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 123-144 10437143-1 1998 AIM: To improve HPLC method for rapid determination of urinary S/R-ratio of mephenytoin, a widely used metabolic index for cytochrome P-450 2C19 (CYP2C19) activity. Mephenytoin 76-87 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 146-153 9797796-0 1998 Bantu Tanzanians have a decreased capacity to metabolize omeprazole and mephenytoin in relation to their CYP2C19 genotype. Mephenytoin 72-83 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 105-112 9817620-5 1998 CYP2C19 is the source of the S-mephenytoin oxidation polymorphism. Mephenytoin 29-42 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 0-7 9864282-12 1998 In addition, when sulfaphenazole was combined with S-mephenytoin, further inhibition of 3alpha-hydroxydesogestrel formation was observed suggesting a possible role for CYP2C19. Mephenytoin 51-64 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 168-175 9732415-0 1998 Identification of new human CYP2C19 alleles (CYP2C19*6 and CYP2C19*2B) in a Caucasian poor metabolizer of mephenytoin. Mephenytoin 106-117 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 45-52 9732415-0 1998 Identification of new human CYP2C19 alleles (CYP2C19*6 and CYP2C19*2B) in a Caucasian poor metabolizer of mephenytoin. Mephenytoin 106-117 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 45-52 9732415-9 1998 The incidence of CYP2C19*6 in a European Caucasian population phenotyped for mephenytoin metabolism was 0/344 (99% confidence limits of 0 to 0.9%). Mephenytoin 77-88 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 17-24 9732415-12 1998 Recombinant CYP2C19 6 had negligible catalytic activity toward S-mephenytoin compared with CYP2C19 1B, which is consistent with the conclusion that CYP2C19*6 represents a PM allele. Mephenytoin 63-76 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 12-19 9755458-3 1998 A well-characterized genetic polymorphism occurs in CYP2C19, which is associated with the 4"-hydroxylation of S-mephenytoin. Mephenytoin 110-123 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 52-59 9695714-5 1998 The disposition of racemic mephenytoin for CYP2C19 and debrisoquin for CYP2D6 were characterized in plasma and urine samples collected over 192 hours. Mephenytoin 27-38 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 43-50 9831966-6 1998 The second type of genetic P450 function tests (CYP2C19 and CYP2D6) involves probe drugs such as S-mephenytoin, catalysed by CYP2C19, and debrisoquine and sparteine, catalysed by CYP2D6. Mephenytoin 97-110 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 48-55 9831966-3 1998 The genetic polymorphism of the CYPs responsible for debrisoquine/ sparteine (CYP2D6) metabolism and S-mephenytoin (CYP2C19) metabolism has been well documented, but information on the impairment of each isoform in liver disease is still limited. Mephenytoin 101-114 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 116-123 9831966-6 1998 The second type of genetic P450 function tests (CYP2C19 and CYP2D6) involves probe drugs such as S-mephenytoin, catalysed by CYP2C19, and debrisoquine and sparteine, catalysed by CYP2D6. Mephenytoin 97-110 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 125-132 9578596-0 1998 Characterization of CYP2C19 and CYP2C9 from human liver: respective roles in microsomal tolbutamide, S-mephenytoin, and omeprazole hydroxylations. Mephenytoin 101-114 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 20-27 9578596-1 1998 Individuals with drug metabolism polymorphisms involving CYP2C enzymes exhibit deficient oxidation of important therapeutic agents, including S-mephenytoin, omeprazole, warfarin, tolbutamide, and nonsteroidal anti-inflammatory drugs. Mephenytoin 142-155 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 57-62 9578596-3 1998 To that end, we purified CYP2C19, CYP2C9, and CYP2C8 from human liver samples using conventional chromatographic techniques and examined their capacity to oxidize S-mephenytoin, omeprazole, and tolbutamide. Mephenytoin 163-176 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 25-32 9578596-4 1998 Upon reconstitution, CYP2C19 metabolized S-mephenytoin and omeprazole at rates that were 11- and 8-fold higher, respectively, than those of intact liver microsomes, whereas neither CYP2C9 nor CYP2C8 displayed appreciable metabolic activity with these substrates. Mephenytoin 41-54 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 21-28 9578596-7 1998 Polyclonal CYP2C19 antibodies markedly decreased S-mephenytoin 4"-hydroxylation (98% inhibition) and omeprazole 5-hydroxylation (85% inhibition) by human liver microsomes. Mephenytoin 49-62 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 11-18 9578596-14 1998 Our results, like those obtained with recombinant CYP2C enzymes, indicate that CYP2C19 is a primary determinant of S-mephenytoin 4"-hydroxylation and low-Km omeprazole 5-hydroxylation in human liver. Mephenytoin 115-128 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 50-55 9578596-14 1998 Our results, like those obtained with recombinant CYP2C enzymes, indicate that CYP2C19 is a primary determinant of S-mephenytoin 4"-hydroxylation and low-Km omeprazole 5-hydroxylation in human liver. Mephenytoin 115-128 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 79-86 10022751-0 1998 An additional defective allele, CYP2C19*5, contributes to the S-mephenytoin poor metabolizer phenotype in Caucasians. Mephenytoin 62-75 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 32-39 10022751-10 1998 The Arg433 to Trp mutation in the heme-binding region essentially abolishes activity of recombinant CYP2C19*5A toward S-mephenytoin and tolbutamide, which is consistent with the conclusion that CYP2C19*5 represents poor metabolizer alleles. Mephenytoin 118-131 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 100-107 10022751-10 1998 The Arg433 to Trp mutation in the heme-binding region essentially abolishes activity of recombinant CYP2C19*5A toward S-mephenytoin and tolbutamide, which is consistent with the conclusion that CYP2C19*5 represents poor metabolizer alleles. Mephenytoin 118-131 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 194-201 9435198-0 1998 A new genetic defect in human CYP2C19: mutation of the initiation codon is responsible for poor metabolism of S-mephenytoin. Mephenytoin 110-123 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 30-37 9352570-5 1997 The exact structure of the conjugate is unknown, but we suggest that an S-N bond between cysteine and S-mephenytoin is formed via an oxidative radical mechanism catalyzed by CYP2C19. Mephenytoin 102-115 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 174-181 9246016-2 1997 Induction is most pronounced in slow metabolizers of S-mephenytoin because CYP2C19 (S-mephenytoin hydroxylase) is responsible for the elimination of omeprazole. Mephenytoin 53-66 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 75-82 10837557-1 1997 This review highlights the present knowledge on the CYP2D6 (sparteine/debrisoquine) and the CYP2C19 (mephenytoin) polymorphisms. Mephenytoin 101-112 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 92-99 9476041-8 1997 Six of the 10 S-mephenytoin poor-metaboliser alleles (60%) carried either the CYP2C19*2 or CYP2C19*3. Mephenytoin 14-27 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 78-85 9224780-4 1997 Both drugs were potent, competitive inhibitors of CYP2C19, as measured by the conversion of S-mephenytoin to 4-hydroxymephenytoin (k(i) = 3.1 +/- 2.2 microM for omeprazole, K(i) = 3.2 +/- 1.3 microM for lansoprazole). Mephenytoin 92-105 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 50-57 9164419-7 1997 CONCLUSIONS: These results suggest that the hydroxylation of lansoprazole cosegregates with the genetically determined S-mephenytoin 4"-hydroxylation (CYP2C19) polymorphism in the Korean subjects. Mephenytoin 119-132 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 151-158 9103550-0 1997 Differences in the incidence of the CYP2C19 polymorphism affecting the S-mephenytoin phenotype in Chinese Han and Bai populations and identification of a new rare CYP2C19 mutant allele. Mephenytoin 71-84 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 36-43 9110363-0 1997 Frequencies of the defective CYP2C19 alleles responsible for the mephenytoin poor metabolizer phenotype in various Oriental, Caucasian, Saudi Arabian and American black populations. Mephenytoin 65-76 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 29-36 9265947-10 1997 Various probe drugs may be used for phenotyping CYP2D6 (debrisoquine, dextromethorphan and sparteine) and CYP2C19 (mephenytoin and omeprazole). Mephenytoin 115-126 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 106-113 9170147-10 1997 Good correlations were found between levels of CYP2C9 and activities of tolbutamide methyl hydroxylation (r = 0.77) and between levels of CYP2C19 and activities of S-mephenytoin 4"-hydroxylation (r = 0.86) in liver microsomes of the human samples examined. Mephenytoin 164-177 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 138-145 9170148-6 1997 The CYP2C19 activity was expressed as the ratio of S/R-mephenytoin (S/R-ratio), the percentage of the dose excreted as 4"-OH-M (D%), and the log10 of the hydroxylation index which was defined as the ratio of micromoles of (S)-mephenytoin dose to micromoles of 4"-OH-M excreted in urine (1g HI). Mephenytoin 222-237 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 4-11 9476041-8 1997 Six of the 10 S-mephenytoin poor-metaboliser alleles (60%) carried either the CYP2C19*2 or CYP2C19*3. Mephenytoin 14-27 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 91-98 8971434-3 1996 The relationship between the oxidative capacities of CYP2C19 for the two substrates, proguanil and mephenytoin, was studied in 39 subjects (two poor and 37 extensive metabolizers of proguanil). Mephenytoin 99-110 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 53-60 8946476-13 1996 Thus, the defect CYP2C19*2 and CYP2C19*3-alleles explained 100% of the 23 Korean poor metabolizers of S-mephenytoin. Mephenytoin 102-115 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 17-24 8988068-9 1996 The genotyping of CYP2C19 discriminates between the two S-mephenytoin 4"-hydroxylation phenotypes completely in the Japanese subjects. Mephenytoin 56-69 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 18-25 8894508-3 1996 5-Hydroxyomeprazole (5OH-OP) formation cosegregates with the polymorphism of (S)-mephenytoin 4"-hydroxylation in humans, which is now known to be mediated by CYP2C19. Mephenytoin 77-92 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 158-165 8986013-2 1996 All patients were extensive metabolizers of mephenytoin (CYP2C19) and dextromethorphan (CYP2D6), except one patient, who had a genetic deficiency of CYP2D6. Mephenytoin 44-55 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 57-64 8873687-5 1996 RESULTS: In the white subjects, omeprazole significantly inhibited CYP2C19-mediated S-mephenytoin metabolism as indicated by decreases in the urinary R/S enantiomeric ratio (63% +/- 13%; p < 0.02; mean +/- SD) and the excretion of 4"-hydroxymephenytoin (39% +/- 13%; p < 0.001). Mephenytoin 84-97 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 67-74 8946476-13 1996 Thus, the defect CYP2C19*2 and CYP2C19*3-alleles explained 100% of the 23 Korean poor metabolizers of S-mephenytoin. Mephenytoin 102-115 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 31-38 8737964-1 1996 The polymorphisms of debrisoquin (CYP2D6) and S-mephenytoin (CYP2C19) hydroxylation were studied in 210 unrelated healthy native Estonians by coadministration of mephenytoin and debrisoquin or dextromethorphan. Mephenytoin 46-59 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 61-68 8807668-0 1996 Evidence that poor metabolizers of (S)-mephenytoin could be identified by haplotypes of CYP2C19 in Japanese. Mephenytoin 35-50 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 88-95 8807668-1 1996 (S)-Mephenytoin is metabolized by CYP2C19. Mephenytoin 0-15 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 34-41 8807668-2 1996 The purpose of this study was to examine availability of phenotyping of poor metabolizers (PMs) of (S)-mephenytoin by polymerase chain reaction (PCR)/restriction enzyme genotyping of CYP2C19 in a Japanese population. Mephenytoin 99-114 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 183-190 8807668-11 1996 Our data indicate that Japanese PMs of (S)-mephenytoin could be identified by PCR-based genotyping of CYP2C19. Mephenytoin 39-54 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 102-109 9165689-3 1996 Differences in the quantitative contribution of these enzymes and in the relative affinities of the substrates explain some of the observed interactions with carbamazepin, diazepam, phenytoin and theophylline and of the impact of the CYP2C19 (mephenytoin) genetic polymorphism. Mephenytoin 243-254 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 234-241 8873219-1 1996 The CYP2C19-associated oxidation polymorphism of mephenytoin was investigated in an Inuit population living in the high Arctic of Canada. Mephenytoin 49-60 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 4-11 8737964-1 1996 The polymorphisms of debrisoquin (CYP2D6) and S-mephenytoin (CYP2C19) hydroxylation were studied in 210 unrelated healthy native Estonians by coadministration of mephenytoin and debrisoquin or dextromethorphan. Mephenytoin 48-59 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 61-68 8653995-4 1996 Significant correlations between the mephenytoin enantiomeric ratio and concentrations of thioridazine and metabolites suggest that cytochrome P450IIC19 could contribute to the biotransformation of thioridazine into yet-unknown metabolites, other than thioridazine 2-SO, thioridazine 2-SO2, or thioridazine 5-SO. Mephenytoin 37-48 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 143-152 8861658-4 1996 Dextromethorphan, debrisoquine and sparteine are good substrates for CYP2D6, whereas the S-enantiomer of mephenytoin is a good substrate for CYP2C19, both being two isozymes of cytochrome P-450. Mephenytoin 105-116 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 141-148 8866915-2 1996 Proguanil (PG) oxidative metabolism to cycloguanil (CG) has been linked to the CYP2C19-mediated genetic polymorphism in S-mephenytoin oxidative metabolism. Mephenytoin 120-133 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 79-86 8858891-7 1996 Two genetic polymorphisms in drug oxidation are well known, the sparteine/debrisoquine (CYP2D6) polymorphism and the mephenytoin oxidation (CYP2C19) polymorphism. Mephenytoin 117-128 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 140-147 8822040-2 1996 Recently, it has been shown that phenytoin and tolbutamide are metabolised by CYP2C9/10 whereas mephenytoin is metabolised by CYP2C19. Mephenytoin 96-107 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 126-133 8703653-2 1995 The 4"-hydroxylation of S-mephenytoin, a representative substrate toward CYP2C19, was competitively inhibited by all the SSRIs and their metabolites studied. Mephenytoin 24-37 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 73-80 8791779-0 1996 Genetic tests which identify the principal defects in CYP2C19 responsible for the polymorphism in mephenytoin metabolism. Mephenytoin 98-109 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 54-61 8013282-6 1994 Substrates for CYP1A (phenacetin and acetanilide), CYP2C (mephenytoin), and CYP2E (chlorzoxazone) had negligible inhibitory effects on the hydroxylation of either tropisetron or ondansetron. Mephenytoin 58-69 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 51-56 8521680-2 1995 The isoenzymes which catalyse the polymorphic hydroxylations of debrisoquine/sparteine and S-mephenytoin are cytochromes P450 2D6 and P450 2C19 (CYP2D6 and CYP2C19), respectively. Mephenytoin 91-104 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 156-163 8521680-9 1995 While CYP2D6 catalyses the metabolism of lipophilic bases only, CYP2C19 is involved in the metabolism of acids (e.g. S-mephenytoin), bases (e.g. imipramine and omeprazole) and neutral drugs (e.g. diazepam). Mephenytoin 117-130 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 64-71 7663530-0 1995 The mephenytoin (cytochrome P450 2C 19) and dextromethorphan (cytochrome P450 2D6) polymorphisms in Saudi Arabians and Filipinos. Mephenytoin 4-15 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 17-38 8846622-4 1995 The CYP2C19 phenotype can be determined clinically by use of either mephenytoin or omeprazole as the probe. Mephenytoin 68-79 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 4-11 7581498-5 1995 We have used mephenytoin, debrisoquine and dapsone as selective probes for the phenotypic measures of activity of CYP2C19, CYP2D6, and CYP3A4, respectively. Mephenytoin 13-24 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 114-121 7604218-4 1995 Recent report showed that the principle defect in S-mephenytoin poor metabolizers is a single base pair (G-->A) mutation in exon 5 of CYP 2C19 resulting in an aberrantly spliced mRNA and a non-functional P450 2C19 protein in liver of S-mephenytoin PM. Mephenytoin 50-63 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 137-145 7604218-4 1995 Recent report showed that the principle defect in S-mephenytoin poor metabolizers is a single base pair (G-->A) mutation in exon 5 of CYP 2C19 resulting in an aberrantly spliced mRNA and a non-functional P450 2C19 protein in liver of S-mephenytoin PM. Mephenytoin 237-250 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 137-145 7704034-11 1994 The enzyme responsible for S-mephenytoin metabolism has been shown to be CYP2C19, and two defects in the CYP2C19 gene have been described in poor metabolizers. Mephenytoin 27-40 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 73-80 7704034-11 1994 The enzyme responsible for S-mephenytoin metabolism has been shown to be CYP2C19, and two defects in the CYP2C19 gene have been described in poor metabolizers. Mephenytoin 27-40 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 105-112 8563772-0 1995 A multifamily study on the relationship between CYP2C19 genotype and s-mephenytoin oxidation phenotype. Mephenytoin 69-82 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 48-55 8563772-1 1995 It has recently been shown that the most common mutation (named m1) in both Caucasian and Japanese poor metabolizers (PM) of S-mephenytoin is a single base pair mutation (G-->A) in exon 5 of the CYP2C19 gene. Mephenytoin 125-138 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 198-205 7554698-0 1995 Comparison of chloroguanide and mephenytoin for the in vivo assessment of genetically determined CYP2C19 activity in humans. Mephenytoin 32-43 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 97-104 7554698-2 1995 An additional objective was to examine the interactions between chloroguanide, omeprazole, and mephenytoin, which are three substrates of CYP2C19. Mephenytoin 95-106 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 138-145 7554698-11 1995 CONCLUSION: Chloroguanide inhibits the CYP2C19-dependent 4"-hydroxylation of mephenytoin. Mephenytoin 77-88 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 39-46 8195181-3 1994 Impaired metabolism of mephenytoin and a number of other currently used drugs results from a defect in a cytochrome P450 enzyme recently identified as CYP2C19. Mephenytoin 23-34 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 151-158 8215410-0 1993 Isolation and characterization of human liver cytochrome P450 2C19: correlation between 2C19 and S-mephenytoin 4"-hydroxylation. Mephenytoin 97-110 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 46-66 34910929-5 2022 In terms of mode of reversible inhibition, vicagrel exhibited mixed-type inhibition of CYP2B6-catalyzed bupropion hydroxylation and noncompetitive inhibition of CYP2C19-mediated S-mephenytoin 4"-hydroxylation with Ki values of 0.19 muM and 1.2 muM, respectively. Mephenytoin 178-191 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 161-168 33060488-8 2021 In the IV-POS group, three patients were poor dextromethorphan (CYP2D6) metabolizers; in the POS-POS group, one was a poor mephenytoin (CYP2C19) metabolizer. Mephenytoin 123-134 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 136-143 31814297-2 2020 This study aimed at evaluating its effect on CYP2D6 and CYP2C19 activities in submitting psychiatric patients to phenotyping with dextromethorphan and mephenytoin, respectively, substrates of these enzymes, before and during a treatment with perazine. Mephenytoin 151-162 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 56-63 33302490-0 2020 A Physiologically-Based Pharmacokinetic (PBPK) Model Network for the Prediction of CYP1A2 and CYP2C19 Drug-Drug-Gene Interactions with Fluvoxamine, Omeprazole, S-mephenytoin, Moclobemide, Tizanidine, Mexiletine, Ethinylestradiol, and Caffeine. Mephenytoin 160-173 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 94-101 30902024-10 2020 In CYP2C19-genotyped human liver microsomes, normeperidine formation was significantly correlated with CYP2C19 activity (S-mephenytoin 4 -hydroxylation). Mephenytoin 121-134 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 3-10 30902024-10 2020 In CYP2C19-genotyped human liver microsomes, normeperidine formation was significantly correlated with CYP2C19 activity (S-mephenytoin 4 -hydroxylation). Mephenytoin 121-134 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 103-110 33115391-3 2020 CYP2C19 metabolizes very important drug such as antiulcer drug omeprazole, the antiplatelet drug clopidogrel and anticonvulsant mephenytoin. Mephenytoin 128-139 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 0-7 29665549-4 2018 METHODS: (S)-Mephenytoin was used to assess CYP2C19 activities in human liver microsomes derived from 114 Hungarian organ donors. Mephenytoin 9-24 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 44-51 30399481-2 2019 Although CYP2C19 isoform is a minor hepatic CYP, it metabolizes clinically important drugs such as omeprazole and S-mephenytoin. Mephenytoin 114-127 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 9-16 30399481-3 2019 In this work, the interaction of purified CYP2C19 WT (CYP2C19) with seven drugs (phenytoin, S-mephenytoin, omeprazole, lansoprazole, cimetidine, propranolol, and warfarin) was investigated using spectroscopic methods. Mephenytoin 92-105 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 42-49 30399481-3 2019 In this work, the interaction of purified CYP2C19 WT (CYP2C19) with seven drugs (phenytoin, S-mephenytoin, omeprazole, lansoprazole, cimetidine, propranolol, and warfarin) was investigated using spectroscopic methods. Mephenytoin 92-105 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 54-61 30399481-8 2019 Phenytoin and S-mephenytoin showed that binding to CYP2C19 occurred in a stepwise manner and that the coordination of a water molecule was facilitated in the second binding step. Mephenytoin 14-27 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 51-58 25845826-5 2015 These data were then used in mechanistic models to predict genotype-dependent disposition of CYP2C19 substrates (i.e., S-mephenytoin, citalopram, pantoprazole, and voriconazole) by incorporating in vivo clearance or pharmacokinetics of wild-type subjects and parameters of other clearance pathways. Mephenytoin 119-132 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 93-100 26021325-8 2015 Poor metabolism of mephenytoin was seen in persons homozygous for both rs12769205 and rs4244285 (CYP2C19*2/*2), but with little effect on mephenytoin disposition of CYP2C19*1/*2, CYP2C19*1/*3, or CYP2C19*1/*35 heterozygous alleles. Mephenytoin 19-30 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 97-104 27128896-3 2016 Aschantin potently inhibited CYP2C8-mediated amodiaquine N-de-ethylation, CYP2C9-mediated diclofenac 4"-hydroxylation, CYP2C19-mediated [S]-mephenytoin 4"-hydroxylation, and CYP3A4-mediated midazolam 1"-hydroxylation, with Ki values of 10.2, 3.7, 5.8, and 12.6 microM, respectively. Mephenytoin 140-151 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 119-126 23241944-3 2013 RESULTS: The rate of generation of human-predominant drug metabolites for S-mephenytoin and diclofenac in the chimeric mice was correlated with the CYP2C19 (n=9 donors, P=0.0005) or CYP2C9 (n=7 donors, P=0.0394) genotype, respectively, of the transplanted human hepatocytes. Mephenytoin 74-87 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 148-155 23318708-4 2013 Kinetic analysis for inhibition revealed that CBD showed a mixed-type inhibition against (S)-mephenytoin 4"-hydroxylation by recombinant CYP2C19. Mephenytoin 89-104 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 137-144 22943175-9 2012 The inhibitory action of glycyrrhetinic acid was observed in CYP2C9 for 4-hydroxylation of diclofenac, CYP2C19 for 4"-hydroxylation of (S)-mephenytoin and CYP3A4 for 1"-hydroxylation of midazolam with half maximal inhibitory concentration (IC50) values of 4.3-fold, 3.8-fold and 9.6-fold higher than specific inhibitors in HLM, respectively. Mephenytoin 135-150 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 103-110 22652334-4 2012 R-fluoxetine and ticlopidine inhibited CYP2C19 activity, as determined using S-mephenytoin as a substrate, and caused 8.7- and 2.3-fold IC(50) shifts, respectively, after pre-incubation. Mephenytoin 77-90 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 39-46 22239545-6 2012 Compound 30 exhibited improved metabolic stability (Cl(int) = 12.4 mL/min/nmol) and was selective in regard to inhibition of CYP2C19-catalyzed (S)-mephenytoin hydroxylation in human liver microsomes. Mephenytoin 143-158 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 125-132 22454664-4 2012 The 4"-hydroxylation of S-mephenytoin, a representative substrate toward CYP2C19, was increased by phenytoin sodium (positive control). Mephenytoin 24-37 cytochrome P450 family 2 subfamily C member 19 Homo sapiens 73-80