?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.title=Amniotic-Fluid+Ingestion+Enhances+the+Central%0D%0AAnalgesic+Effect+of+Morphine&rft.creator=DiPirro%2C+Jean+M.&rft.creator=Thompson%2C+Alexis+C.&rft.creator=Kristal%2C+Dr.+Mark+B.&rft.subject=Psychobiology&rft.subject=Physiological+Psychology&rft.subject=Neuropharmacology&rft.subject=Behavioral+Neuroscience&rft.description=Amniotic+fluid+and+placenta+contain+a+substance+(POEF)+that+when+ingested+enhances+opioid-mediated+analgesia+produced+by+several+agents+(morphine+injection%2C+vaginal%2Fcervical+stimulation%2C+late+pregnancy%2C+footshock)%2C+but+not+that+produced+by+aspirin+injection.+The+present+series+of+experiments+employed+quaternary+naltrexone%2C+an+opioid+antagonist+that+does+not+readily+cross+the+blood-brain+barrier%2C+in+conjunction+with+either+peripheral+or+central+administration+of+morphine%2C+to+determine+whether+amniotic-fluid+ingestion+(and+therefore+POEF+ingestion)+enhances+opioid-mediated+analgesia+by+affecting+the+central+and%2For+peripheral+actions+of+morphine.+The+results+suggest+that+POEF+affects+only+the+central+analgesic+effects+of+morphine.&rft.publisher=Pergamon+Press&rft.date=1991&rft.type=Journal+(Paginated)&rft.type=PeerReviewed&rft.format=application%2Fpdf&rft.identifier=http%3A%2F%2Fcogprints.org%2F6211%2F1%2Fcentral.pdf&rft.identifier=++DiPirro%2C+Jean+M.+and+Thompson%2C+Alexis+C.+and+Kristal%2C+Dr.+Mark+B.++(1991)+Amniotic-Fluid+Ingestion+Enhances+the+Central+Analgesic+Effect+of+Morphine.++%5BJournal+(Paginated)%5D+++++&rft.relation=http%3A%2F%2Fcogprints.org%2F6211%2F