title: Age-rated profile of cardiovascular reactivity to norepinephrine and angiotensin II in normal and hypertensive man.
abstract: The interrelationships among age, cardiovascular pressor reactivity to intravenously infused norepinephrine (NE) or angiotensin II, and endogenous plasma NE or renin (PRA) levels were evaluated i 31 normal subjects and 37 patients with essential hypertension. In normal subjects both angiotensin II pressor dose and PRA decreased progressively with aging. Angiotensin pressor dose correlated positively with PRA (r = 0.41, P < 0.025) and inversely with age (r = -0.46, P < 0.02). NE pressor dose and basal plasma NE were also positively correlated (r = 0.53, P < 0.005), but the two factors remained largely unchanged with aging. Findings in essential hypertension differed in certain aspects. Angiotensin II pressor dose did not correlate with either basal PRA or age; and pressor doses of NE and angiotensin II tended to be lower in some patients than in normal subjects. These findings indicate that aging is accompanied by a physiologic increase in cardiovascular reactivity to angiotensin II, probably due to a concomitant decrease in circulating renin. The dissociation between angiotensin pressor dose and PRA in essential hypertension suggests an interference from an other factor.
mesh_terms: D000328:Adult; D000375:Aging; D000804:Angiotensin II / Q000494:pharmacology*; D005260:Female; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D006973:Hypertension / Q000503:physiopathology*; D008297:Male; D009638:Norepinephrine / Q000494:pharmacology*
chemical_list: D000804:Angiotensin II; D009638:Norepinephrine