PMID-sentid Pub_year Sent_text comp_official_name comp_offsetprotein_name organism prot_offset 12834028-11 2003 In addition, deprivation of endogenous estrogens, by blocking their formation using the aromatase inhibitor letrozole, induced OT hypo-responsiveness comparable to that observed in hypo rabbits. Letrozole 108-117 oxytocin Oryctolagus cuniculus 127-129