?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.title=Participation+of+Placental+Opioid-Enhancing+Factor+in+opioid-modulated+events+at+parturition&rft.creator=Kristal%2C+M.+B.&rft.subject=Behavioral+Neuroscience&rft.subject=Behavioral+Biology&rft.subject=Comparative+Psychology&rft.subject=Neurochemistry&rft.subject=Neuroendocrinology&rft.subject=Neuropharmacology&rft.subject=Physiological+Psychology&rft.subject=Psychobiology&rft.description=Parturition+in+mammals+occurs+in+the+context+of+sensory%2C+neurochemical%2C+and+endocrinological+factors+that+are+orchestrated+and+timed+so+that+maternal+behavior+and+the+object+of+the+behavior%2C+the+neonate%2C+%22emerge%22+almost+simultaneously.+Among+the+factors+found+to+be+important+for+the+suppression+of+pain+during+delivery+as+well+as+for+the+emergence+of+caretaking+behavior+toward+the+young%2C+are+changes+in+endogenous+opioid+activity+in+the+central+nervous+system.+In+most+mammalian+species%2C+these+changes+are+likely+initiated+by+sensory+events+arising+in+the+distended+reproductive+tract+and+abdominal+musculature%2C+and+are+modified+by+the+parturitional+endocrine+milieu+and+substances+ingested+in+amniotic+fluid+and+placenta+(e.g.%2C+Placental+Opioid-Enhancing+Factor%2C+or+POEF).+In+addition%2C+ingestion+of+afterbirth+material+may+decrease+the+probability+that+the+vaginal%2Fcervical+sensory+stimulation+arising+during+delivery+will+trigger+pseudopregnancy%2C+a+condition+that+decreases%2C+if+not+eliminates%2C+the+likelihood+of+fertilization+in+the+postpartum+estrus.+The+research+described+herein+primarily+focuses+on+elucidating+the+manner+in+which+POEF+modulates+opioid+antinociception%2C+and+otherwise+participates+in+opioid-mediated+parturitional+events.&rft.publisher=The+International+Association+for+Biomedical+Sciences%2C+Mie%2C+Japan&rft.date=1998&rft.type=Conference+Paper&rft.type=NonPeerReviewed&rft.format=text%2Fhtml&rft.identifier=http%3A%2F%2Fcogprints.org%2F69%2F1%2Fpoef.html&rft.identifier=++Kristal%2C+M.+B.++(1998)+Participation+of+Placental+Opioid-Enhancing+Factor+in+opioid-modulated+events+at+parturition.++%5BConference+Paper%5D+++++&rft.relation=http%3A%2F%2Fcogprints.org%2F69%2F