title: Absence of morphine antagonism of prostaglandin E1-stimulated [3H]3',5'-cyclic adenosine monophosphate accumulation in a rat brain mince system.
abstract: Prostaglandin E1 (PGE1)-stimulated [3H]3',5'-cyclic adenosine monophosphate ([3H]cAMP) accumulation was studied in a rat brain mince system to determine if stimulation of net [3H]cAMP accumulation could be prevented or reversed by morphine. Incubated minces of whole brain minus cerebellum were prepared from naive, acutely morphine-treated, and morphine-tolerant and withdrawing rats. Basal levels of [3H]cAMP accumulation in the three groups were equal within experimental limits. Morphine addition to the PGE1-stimulated minces did not prevent or reverse stimulation of [3H]cAMP accumulation in any of the three experimental groups. The data do not support the thesis that PGE1-stimulated cAMP accumulation in brain is a locus of opiate action in the phenomena of opiate analgesia, tolerance, and dependence.
mesh_terms: D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D000242:Cyclic AMP / Q000378:metabolism*; D004361:Drug Tolerance; D006801:Humans; D008297:Male; D009020:Morphine / Q000494:pharmacology; D009021:Morphine Dependence / Q000378:metabolism; D009270:Naloxone; D011458:Prostaglandins E / Q000494:pharmacology*; D051381:Rats; D013375:Substance Withdrawal Syndrome / Q000139:chemically induced
chemical_list: D011458:Prostaglandins E; D009270:Naloxone; D009020:Morphine; D000242:Cyclic AMP