?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.title=Placenta+ingestion+enhances+opiate+analgesia+in+rats.&rft.creator=Kristal%2C+Dr.+Mark+B.&rft.creator=Thompson%2C+A.+C.&rft.creator=Grishkat%2C+H.L.&rft.subject=Behavioral+Neuroscience&rft.description=Analgesia%2C+produced+by+either+a+morphine+injection+or+footshock%2C+was+monitored+(using+a+tail-flick+test)+in+nonpregnant+female+rats.+Analgesia+was+induced+within+minutes+of+having+the+rats+eat+on+of+several+substances.+When+the+substance+eaten+was+rat+placenta%2C+both+the+morphine-+and+shock-induced+types+of+analgesia+were+significantly+grater+than+in+controls+that+ingested+other+substances+(or+nothing).+When+footshock+(hind-paw)+was+administered+in+conjunction+with+the+opiate+antagonist+naltrexone%2C+the+analgesia+produced+was+attenuated+but+detectable%3B+in+this+case%2C+placenta+ingestion+did+not+enhance+the+analgesia%2C+suggesting+that+the+effect+of+placenta+is+specific+to+opiate-mediated+analgesia.+It+is+possible+that+this+enhancement+of+analgesia+is+one+of+the+principal+benefits+to+mammalian+mothers+of+ingesting+placenta+and+birth+fluids+(placentophagia)+at+delivery.&rft.publisher=Pergamon+Press&rft.date=1985&rft.type=Journal+(Paginated)&rft.type=PeerReviewed&rft.format=application%2Fpdf&rft.identifier=http%3A%2F%2Fcogprints.org%2F5764%2F1%2Fpoef85.pdf&rft.identifier=++Kristal%2C+Dr.+Mark+B.+and+Thompson%2C+A.+C.+and+Grishkat%2C+H.L.++(1985)+Placenta+ingestion+enhances+opiate+analgesia+in+rats.++%5BJournal+(Paginated)%5D+++++&rft.relation=http%3A%2F%2Fcogprints.org%2F5764%2F