[Changes in reactivity of the renin-angiotensin-aldosterone system in old age as a risk factor in the development of hypertension].

The sensitivity of the renin-angiotensin-aldosterone system (RAAS) to regulatory sympathoadrenal and hypothalamo-pituitary effects was shown to increase with advancing age, in spite of declining plasma renin and aldosterone baselines. At the same time, this humoral mechanism was no longer capable of responding as adequately to potent stimuli, such as submaximum physical stress. The data obtained suggest that the RASS might act as a trigger mechanism underlying a greater incidence of essential hypertension in old age.