title: Effect of normorphine and enkephalin on spontaneous potentials in the vas deferens.
abstract: Spontaneous excitatory junction potentials were recorded intracellularly from the smooth muscle of the mouse vas deferens. Exposure of the vas deferens to either normorphine (1 muM) or methionine-enkephalin (0.5 muM) did not alter the frequency or amplitude distribution of the spontaneous potentials. The possible mechanisms by which the narcotic agonists depress the release of noradrenaline on nerve stimulation without inhibiting the spontaneous release of noradrenaline are discussed.
mesh_terms: D000818:Animals; D066298:In Vitro Techniques; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects*; D051379:Mice; D009022:Morphine Derivatives / Q000494:pharmacology*; D009130:Muscle, Smooth / Q000187:drug effects; D009419:Nerve Tissue Proteins / Q000494:pharmacology; D009469:Neuromuscular Junction / Q000187:drug effects; D009638:Norepinephrine / Q000378:metabolism; D010455:Peptides / Q000494:pharmacology*; D011957:Receptors, Opioid / Q000187:drug effects; D009435:Synaptic Transmission / Q000187:drug effects; D014649:Vas Deferens / Q000187:drug effects
chemical_list: D009022:Morphine Derivatives; D009419:Nerve Tissue Proteins; D010455:Peptides; D011957:Receptors, Opioid; D009638:Norepinephrine