Effects of Chronic Treatment with Angiotensin II on Thermoregulation in Rats

Angiotensin (Ang) I1 is a peptide with multiple physiologic roles, one of the best known of which is vasoconstriction. However, when administered acutely to restrained rats, it unexpectedly elevates tail skin temperature and reduces metabolic rate. As a consequence, core body temperature decreases.' The central nervous system seems to be involved in this effect of Ang 11. Thus, lesion of the subfornical organ attenuates and central administration of Ang I1 mimics the action of peripheral Ang II.2,3 Chronic peripheral administration of Ang I1 produces upregulation of brain Ang I1 receptor^.^ In the present study, we examined the effects of acute and chronic administration of Ang I1 on body temperature and activity of freely moving rats.5