Veratramine-induced behavior associated with serotonergic hyperfunction in mice.

Abstract

ABSTRACT-The administration of veratramine produced generalized tremor, myoclonus, hindlimb abduction, backward gait and Straub tail, similar to the "5-hydroxytryptamine (5-HT) syndrome", in mice. Pretreatment with metergoline, methysergide, mianserin or cyproheptadine ameliorated veratramine-induced myoclonus and tremor. For suppression of other symptoms, mianserin and cyproheptadine were effective. Metergoline improved hindlimb abduction and Straub tail, but did not inhibit backward gait. Methysergide was ineffective for the remaining symptoms. 5-Methoxy-N,Ndimethyltryptamine (5-MeODMT) enhanced all these symptoms except for Straub tail. 8-Hydroxy-2-[di-n-propylamino] tetralin hydrobromide (8-OH-DPAT) augmented tremor, hindlimb abduction and backward gait, but did not influence myoclonus and Straub tail. 5-Methoxy-3[1,2,3,6-tetrahydropyridin-4-yl] 1H-indole (RU 24969) did not modify the symptoms. Destruction of 5-HT neurons using 5,6-dihydroxytryptamine (5,6-DHT) resulted in suppression of the syndrome. The denervation supersensitivity caused by 5,6-DHT did not increase the response to veratramine. These findings indicate that part of the site of action of veratramine may be the presynaptic 5-HT neurons.

Morphine-induced Straub tail reaction as a model of spasticity in mice: effects of serotonergic compounds

“…Возможно, что отсутствие влияния на выраженность реакции Штрауба связано и с тем, что метисергид также является агонистом 5-HT 1 -рецепторов [23]. Неэффективность метисергида, в отличие от ципрогептадина, отмечали также в экспериментах, где реакция Штрауба была вызвана введением вератрамина [24].…”

Liliaceae Juss.

“…Brief but very potent binding and modifi cation of Na + channels lasts several seconds, followed by slow inactivation thereafter (Leibowitz et al 1987 ;Strichartz et al 1987 ;Nanasi et al 1990 ). At least some of the effects may be mediated through serotonin activity (Nagata and Izumi 1991 ). All excitable cells are affected but most particularly afferent nerve endings, resulting in increased sensitivity, intensifi ed activity, or even paralysis at high concentrations.…”

Design, synthesis, and biological evaluation of estrone-derived hedgehog signaling inhibitors

“…xx Unlike cyclopamine, 2 does not act as an SHH antagonist, and causes hemolysis by targeting other receptors. xxi …”