Functional activity of the sympathoadrenal system in hypertensive NISAG rats

Abstract

NISAG rats with stress-induced arterial hypertension are characterized by hyperactivity of the sympathoadrenal system under rest conditions and during stress exposure.

Age-related structural characteristics of the adrenal medulla in hypertensive NISAG rats

“…The increased emotional excitability of NISAG rat pups results in frequent episodes of BP elevation and, therefore, development of arterial hypertension. Morphological signs are consistent with physiological characteristics of hormonal activity of the adrenal medulla in NISAG rats [4]. Epinephrine concentration in the adrenal gland of NISAG rats 2-fold exceeds that in Wistar rats.…”

“…Epinephrine concentration in the adrenal gland of NISAG rats 2-fold exceeds that in Wistar rats. Moreover, expression of tyrosine hydroxylase gene (key enzyme of catecholamine biosynthesis) increases in the adrenal gland of NISAG rats [4]. These animals are also characterized by high activity of phenylethanolamine N-methyltransferase [5].…”

“…Signs of hyperplasia of the adrenal medulla were most pronounced in adult hypertensive animals with persistent arterial hypertension, as well as during the period of late ontogeny.The development of arterial hypertension in NISAG rats with hereditary stress-induced arterial hypertension [3] is related to hyperactivity of the sympathoadrenal and pituitary-adrenocortical systems playing a role in the stress response [4,5]. Previous studies showed that these animals are characterized by adrenocortical hyperplasia [1,2].…”

Sex-specific peculiarities of cholinergic regulation of the cardiovascular system in normal and hypertensive rats

“…Obviously, vasoconstrictor effects on blood vessels increased under conditions of cholinergic system blockade. Since adrenal production of epinephrine inducing lasting depressive reactions in hypertensive rats [3] sharply increases in hypertension [4], hypertension, more pronounced in males, is associated with more manifest hypotensive reactions to atropine.…”

“…This can be explained by increased sympathoadrenal activity in hypertension [4,6,11] and impaired synthesis of NO in health augmenting the cholinergic effects [10]. More benign form of hypertension in females was associated with significant reduction of the hypotensive effects of ACC.…”