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Short-Duration Hypothermia Induction in Rats using Models for Studies examining Clinical Relevance and Mechanisms
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Short-Duration Hypothermia Induction in Rats using Models for Studies examining Clinical Relevance and Mechanisms

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Influence of alpha-adrenoceptor agonists and antagonists on imipramine-induced hypothermia in mice

Mohammad-Reza Zarrindast1, Sheyda Sadeghi, Mousa Sahebgharani

  • 1Department of Pharmacology, School of Medicine, Tehran University of Medical Science, Tehran, Iran. zarinmr@ams.ac.ir

Pharmacology & Toxicology
|June 28, 2003
PubMed

Effects of adrenoceptor agonists and antagonists on imipramine-induced hypothermia in mice were studied. Intraperitoneal injection of imipramine (10-40 mg x kg(-1)), alpha2-adrenoceptor agonist clonidine (0.05-0.1 mg x kg(-1)), alpha1-adrenoceptor agonist phenylephrine (6 mg x kg(-1)) and alpha1-adrenoceptor antagonist prazosin (1-4 mg x kg(-1)) but not alpha2-adrenoceptor antagonist yohimbine (1-4 mg x kg(-1)) induced significant hypothermia. The hypothermic response induced by imipramine (10-30 mg x kg(-1)) was not altered by clonidine (0.05-0.1 mg x kg(-1)) or phenylephrine (2-6 mg x kg(-1)). The response of imipramine (10-30 mg x kg(-1)) was reduced significantly by yohimbine (2 mg x kg(-1)) and was potentiated by prazosin (1 mg x kg(-1)). The hypothermic effect of clonidine (0.1 mg x kg(-1)) and imipramine (20 mg x kg(-1)) were also decreased significantly by different doses of yohimbine (1-4 mg x kg(-1)). The hypothermia induced by different doses of prazosin (1-4 mg x kg(-1)) was not altered by yohimbine (2 mg x kg(-1)) or by low dose of imipramine (10 mg x kg(-1)). It is concluded that alpha2-adrenoceptor mechanism may be involved in the hypothermic effect of imipramine.

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