title: Opioid receptors of human placental villi modulate acetylcholine release.
abstract: The human placental villous tissue contains components of the cholinergic system and opioid receptors of the kappa type. In vitro stimulation of the villous tissue releases acetylcholine in organ baths. A selective kappa agonist, ethylketocyclazocine, inhibits the release of acetylcholine. This inhibition is reversed by the antagonist Mr 2266. The antagonist alone stimulates the release of acetylcholine 18-fold over control. These results demonstrate an interaction between the placental opioid receptors and the cholinergic system in a non-neural tissue. The modulation of acetylcholine release by endogenous opioid peptides could be one of the in vivo functions of placental opioid receptors.
mesh_terms: D000109:Acetylcholine / Q000037:antagonists & inhibitors / Q000502:physiology*; D000818:Animals; D001575:Benzomorphans / Q000494:pharmacology; D003496:Cyclazocine / Q000031:analogs & derivatives / Q000494:pharmacology; D004723:Endorphins / Q000502:physiology; D016314:Ethylketocyclazocine; D006801:Humans; D009924:Organ Culture Techniques; D010920:Placenta / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D011957:Receptors, Opioid / Q000187:drug effects / Q000502:physiology*
chemical_list: D001575:Benzomorphans; D004723:Endorphins; D011957:Receptors, Opioid; C027247:MR 2266; D016314:Ethylketocyclazocine; D003496:Cyclazocine; D000109:Acetylcholine