title: Placental opioid-enhancing factor (POEF): generalizability of effects.
abstract: A substance in amniotic fluid and placenta (POEF for Placental Opioid-Enhancing Factor) has been shown to enhance opiate- or opioid-mediated analgesia in rats. Recent studies have only touched on the generalizability of the phenomenon. The present studies further tested the generalizability of the POEF effect: they examined sex specificity of the mechanism; whether POEF activity exists in afterbirth material of species other than the rat; whether POEF activity exists in tissue other than afterbirth material; whether POEF activity could be demonstrated after injection rather than ingestion of afterbirth material; and whether POEF enhances all opioid-mediated phenomena. We found that (a) POEF is effective in male rats as well as in female rats; (b) POEF activity exists in human and dolphin afterbirth material; (c) ingestion of pregnant-rat liver does not produce enhancement of opioid-mediated analgesia; (d) POEF does not seem to be effective when amniotic fluid is injected either IP or SC; and (e) POEF does not modify morphine-induced hyperthermia.
authors.affiliation: Department of Psychology, State University of New York, Buffalo 14260.
authors.forename: P
authors.initials: P
authors.lastname: Abbott
authors.forename: A C
authors.initials: AC
authors.lastname: Thompson
authors.forename: E J
authors.initials: EJ
authors.lastname: Ferguson
authors.forename: J C
authors.initials: JC
authors.lastname: Doerr
authors.forename: J A
authors.initials: JA
authors.lastname: Tarapacki
authors.forename: P J
authors.initials: PJ
authors.lastname: Kostyniak
authors.forename: J A
authors.initials: JA
authors.lastname: Syracuse
authors.forename: D M
authors.initials: DM
authors.lastname: Cartonia
authors.forename: M B
authors.initials: MB
authors.lastname: Kristal
mesh_terms: D000818:Animals; D001833:Body Temperature Regulation / Q000187:drug effects; D004289:Dolphins; D004723:Endorphins / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D009020:Morphine / Q000494:pharmacology; D009619:Nociceptors / Q000187:drug effects*; D011257:Pregnancy Proteins / Q000494:pharmacology*; D051381:Rats; D011930:Reaction Time / Q000187:drug effects; D011957:Receptors, Opioid / Q000187:drug effects*; D012684:Sensory Thresholds / Q000187:drug effects; D013045:Species Specificity
chemical_list: D004723:Endorphins; D011257:Pregnancy Proteins; D011957:Receptors, Opioid; D009020:Morphine