title: Beta-endorphin suppression of acute morphine abstinence in morphine dependent monkeys: effective given intraventricularly but ineffective given intravenously.
abstract: Six female adult Macaca mulatta monkeys were made dependent upon morphine sulfate and were implanted with a chronic indwelling needle in the lateral ventricle of the brain for sterile intraventricular injections. Both beta-endorphin and morphine, in a dose dependent manner given intraventricularly suppressed the signs of 14 hour acute morphine abstinence. On a molar basis, beta-endorphin was more active than morphine in suppressing the signs of morphine abstinence. When given intravenously in much larger doses, beta-endorphin was ineffective in contrast to morphine which was effective in suppressing abstinence.
authors.forename: E F
authors.initials: EF
authors.lastname: Domino
authors.forename: C H
authors.initials: CH
authors.lastname: Li
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism; D002552:Cerebral Ventricles / Q000187:drug effects / Q000503:physiopathology*; D004305:Dose-Response Relationship, Drug; D004723:Endorphins / Q000008:administration & dosage* / Q000494:pharmacology; D005260:Female; D000882:Haplorhini; D007275:Injections, Intravenous; D007276:Injections, Intraventricular; D007700:Kinetics; D008793:Metrizamide / Q000378:metabolism; D009020:Morphine / Q000494:pharmacology; D009021:Morphine Dependence / Q000503:physiopathology*; D013997:Time Factors; D001615:beta-Endorphin
chemical_list: D004723:Endorphins; D001615:beta-Endorphin; D009020:Morphine; D008793:Metrizamide