title: Effect of clonidine and chlorpromazine on centrally evoked electrodermal responses and their interaction with yohimbine.
abstract: Both clonidine and chlorpromazine reduced the amplitude of electrodermal responses (EDR) evoked by stimulation of the hypothalamus at a constant submaximal frequency (10-16 Hz). The ED50 for clonidine was approximately 5 mug/kg and that for chlorpromazine was about 1 mg/kg. Yohimbine pretreatment (0.5 mg/kg, i.v.) antagonized the effects of clonidine but did not alter the effectiveness of clorpromazine in inhibiting these responses. Yohimbine alone was without effect on these sympathetic-cholinergic responses. These results suggest that clonidine and chlorpromazine deress central sympathetic reactivity by different mechanisms.
mesh_terms: D000818:Animals; D002415:Cats; D002746:Chlorpromazine / Q000494:pharmacology*; D003000:Clonidine / Q000494:pharmacology*; D004347:Drug Interactions; D004558:Electric Stimulation; D005712:Galvanic Skin Response / Q000187:drug effects*; D007031:Hypothalamus / Q000502:physiology; D013997:Time Factors; D015016:Yohimbine / Q000494:pharmacology*
chemical_list: D015016:Yohimbine; D003000:Clonidine; D002746:Chlorpromazine