title: Enkephalinase inhibition suppresses naloxone-induced jumping in morphine-dependent mice.
abstract: The effect of the enkephalinase inhibitor phosphoramidon on the withdrawal syndrome following acute and chronic morphine-induced physical dependence in mice, was investigated. Phosphoramidon administered intracerebroventricularly (50-200 micrograms) suppressed significantly the naloxone-precipitated withdrawal jumping and wet dog shakes while forelimb shakes were potentiated in both acute and chronic morphine-dependent mice. It is suggested that increased saturation of the opioid receptors by endogenous opioid peptides following enkephalinase inhibition, might suppress the severity of the withdrawal syndrome.
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D010450:Endopeptidases; D006020:Glycopeptides / Q000494:pharmacology*; D007276:Injections, Intraventricular; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D009021:Morphine Dependence / Q000523:psychology*; D009270:Naloxone / Q000037:antagonists & inhibitors*; D015260:Neprilysin; D011480:Protease Inhibitors; D013375:Substance Withdrawal Syndrome / Q000523:psychology
chemical_list: D006020:Glycopeptides; D011480:Protease Inhibitors; D009270:Naloxone; D010450:Endopeptidases; D015260:Neprilysin; C008890:phosphoramidon