title: Mu opiate isoreceptors: differentiation with kappa agonists.
abstract: In vivo pharmacological data support the concept of mu (mu) isoreceptors in the rat CNS. The mu 1 receptor mediates analgesia and regulation of cholinergic neurons. Naloxazone may be a specific antagonist of this receptor type. In contrast, the mu 2 receptor is responsible for respiratory depression and regulation of nigrostriatal dopaminergic neurons. In this case, the kappa agonists EKC and MR-2034 appear to be specific mu 2 antagonists.
mesh_terms: D000109:Acetylcholine / Q000378:metabolism; D000701:Analgesics, Opioid / Q000494:pharmacology*; D000818:Animals; D001575:Benzomorphans / Q000031:analogs & derivatives / Q000494:pharmacology*; D001921:Brain / Q000187:drug effects; D003342:Corpus Striatum / Q000502:physiology*; D003496:Cyclazocine / Q000031:analogs & derivatives* / Q000494:pharmacology; D016314:Ethylketocyclazocine; D006624:Hippocampus / Q000502:physiology*; D008297:Male; D008691:Methadone / Q000494:pharmacology; D009019:Morphinans / Q000494:pharmacology*; D009020:Morphine / Q000494:pharmacology; D010296:Parietal Lobe / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D011957:Receptors, Opioid / Q000187:drug effects / Q000502:physiology*; D017465:Receptors, Opioid, delta; D017473:Receptors, Opioid, kappa; D017450:Receptors, Opioid, mu
chemical_list: D000701:Analgesics, Opioid; D001575:Benzomorphans; D009019:Morphinans; D011957:Receptors, Opioid; D017465:Receptors, Opioid, delta; D017473:Receptors, Opioid, kappa; D017450:Receptors, Opioid, mu; C032478:MR 2034; D016314:Ethylketocyclazocine; D009020:Morphine; D003496:Cyclazocine; D000109:Acetylcholine; D008691:Methadone