Interrelations between age and plasma renin, aldosterone and cortisol, urinary catecholamines, and the body sodium/volume state in normal man

Abstract

Interrelations between age and plasma renin, aldosterone and cortisol levels, urinary catecholamiens, plasma and blood volumes, exchangeable body sodium and blood pressure wwere studied in 28 young (19 to 29 years), 16 middle-aged (32 to 58 years) and 15 elderly (60 to 74 years) healthy subjects. Supine and upright plasma renin and supine aldosterone levels decreased while urinary noradrenaline excretion rate increased progressively with aging (r= greater than 0.34; p less than 0.05), with significant differences in mean values between young and elderly subjects (p less than 0.02). There was also an age-related decrease in upright plasma aldosterone concentration, although this was no statistically significant. Furthermore, mean plasma cortisol concentrations increased in response to upright posture in elderly ( + 50%; p less than 0.02), but not in young ( --10%) or middle-aged ( --8%) subjects. Blood pressure correlated with age ( r =0.35; p less than 0.05) or noradrenaline excretion rate ( r= 0.34) in the entire study population and with blood volume in the elderly ( r = 0.68), but not in the young or middle-aged study. Groups. There were no significant age-related differences in the body sodium/volume state, basal plasma cortisol levels or urinary adrenaline excretion rate, and plasma renin or aldosterone levels did not correlate with these parameters or with blood pressure. It is concluded that the influence of age on plasma renin or aldosterone levels, plasma cortisol responsiveness to upright posture, and urinary noradrenaline excretion should be taken into consideration, whenever these factors have to be interpreted in patients with arterial hypertension or other clinical disorders. Further more, these data are conssitent with the possiblity that in normal man increases in supine blood pressure with aging may be related at least partly to concomitant changes in free peripheral noradrenaline.

Pressor factors and cardiovascular pressor responsiveness in borderline hypertension.

“…The rare occurrence of abnormal PRA and NE values in H patients contrasts somewhat with certain previous reports. *" 8 Differences in renin interpretation could possibly be related to patient selection and the lack of age-related normal ranges 11 in other studies; 7 ' 8 however, except for the use of different methodology, we have no explanation for isolated observations of a distinct increase in circulating NE in borderline hypertension. 6 e Nevertheless, it is conceivable that plasma renin or norepinephrine levels could vary with the duration of borderline BP elevations.…”

Norepinephrine in urine and plasma following provocative maneuvers in normal and hypertensive subjects.

“…Increases in UNE excretion with age have been described previously by Weidmann and colleagues; 7 in their study, however, the effect of sex was not examined. Cuche et al 31 were unable to correlate UNE excretion with age in a study of 10 normotertsive and hypertensive subjects.…”

“…Our results extend previous observations that age and sex exert important influences on UNE excretion. 7 ' 8 The state of body fluid volume and posture influence both UNE and PNE.…”

Plasma renin activity and albumin excretion in teenage type I diabetic subjects. A prospective study.

“…2021 These levels continue until a final decline occurs in the forties. 22 High levels of supine and stimulated PRA have been recently reported 23 in seven IDDS, 12.5-19 years of age, in association with elevated Hb Ai c , compared with normal levels in seven age-matched IDDS with normal Hb A )c and in seven age-matched healthy subjects. In the present study PRA was not significantly associated with Hb A,.…”