title: 5-Hydroxytryptamine (5-HT)-dependent myoclonus in guinea pigs is induced through brainstem 5-HT-1 receptors.
abstract: Myoclonic jerking in guinea pigs originates from the brainstem. Indole-containing 5-hydroxytryptamine (5-HT) agonists, but not piperazine-containing 5-HT agonists, induced myoclonus in guinea pigs at pharmacologically relevant doses. Guinea pig brainstem preparations possessed specific binding sites for [3H]5-HT but specific [3H]spiperone binding was low and inconsistent. 5-HT-1 receptors appear to predominate in this tissue. High affinity [3H]5-HT binding was potently displaced by indole-containing 5-HT agonists but only weakly displaced by piperazine-containing 5-HT agonists. The [3H]5-HT specific binding site in guinea pig brainstem responsible for the induction of indoleamine-dependent myoclonus has the characteristics of a 5-HT-1 receptor.
mesh_terms: D000818:Animals; D001665:Binding Sites; D001667:Binding, Competitive; D001933:Brain Stem / Q000378:metabolism / Q000503:physiopathology*; D005260:Female; D006168:Guinea Pigs; D009207:Myoclonus / Q000503:physiopathology*; D011985:Receptors, Serotonin / Q000502:physiology*; D012701:Serotonin / Q000378:metabolism / Q000502:physiology*; D013134:Spiperone / Q000378:metabolism
chemical_list: D011985:Receptors, Serotonin; D012701:Serotonin; D013134:Spiperone