[Angiotensin II in the mechanisms of hypothalamic pressor reactions].

The influence of intracerebroventricular injections of the angiotensin II antagonist--saralasin on the cardiovascular reactions elicited by electrical stimulation of different structures of the hypothalamus in rabbit was studied. The saralasin in doses from 1 to 1.5 mg reduced arterial pressure by 9 +/- 0.2 mm Hg and decreased the amplitude of the hypertensive reactions elicited by electrical stimulation of the paraventricular, supraoptic, ventromedial, supramammillary nucleus of the hypothalamus, area hypothalamic anterior and lateral. It has been shown that most suppressing influence of the saralasin on amplitude of the hypertensive reactions elicited by electrical stimulation of the paraventricular (68%) and supraoptic (76%) nucleus of the hypothalamus which contain magnocellular neurosecretory neurons.