Temperature Regulation pp 261-265 | Cite as
The Tail of the Rat in Temperature Regulation: Effect of Angiotensin II
Summary
The importance of the tail in thermoregulation of the rat was shown by comparison of the colonic temperatures (Tc) of tailed and tailless rats following administration of graded doses of the beta-adrenoceptor agonist, isoproterenol (ISO). The hyperthermic responses of tailless rats was higher and lasted longer than that of tailed controls. Angiotensin II (AngII), a potent vasoconstrictor agent, also increased tail skin temperature (Tsk), but reduced Tc in a dose-related fashion. This apparently aberrant vasodilatory response of tail skin vasculature to a vasoconstrictor agent is mediated by way of AT-1 receptors, since it is blockable by losartan potassium, a specific AT-1 receptor antagonist. The mechanism beyond the AT-1 receptor by which AngII induces a hypothermic response in the rat remains to be elucidated.
Keywords
Losartan Potassium Total Body Surface Area Minute Figure Hypothermic Response Colonic TemperaturePreview
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