[Diurnal variation in the urinary excretion of vanilmandelic acid and aldosterone in normal and hypertensive persons (author's transl)].

The excretion of creatinine, VMA, and aldosterone was measured in the urine of 14 normal and 25 persons with stable essential hypertension during a day time (7.00-23.00 hrs) and a night time (23.00-7.00 hrs) period. Excretion of VMA and aldosterone per hour in the two groups was lower during the night period than during the day. No significant difference existed between the excretion values of both groups. Night/day rations for the excretion of VMA and of aldosterone respectively, per mg of creatinine excreted were calculated for each subject. In the normal group the night/day ratios of aldosterone excretion showed a significant correlation to the corresponding ratios of VMA excretion; such correlation was not found in the hypertensive group. The fact that a correlation was observed in the normal group is compatible with the hypothesis that catecholamines are involved in the regulation of the renin-angiotensin-aldosterone system. Lack of correlation in the group of hypertensive does not as yet allow any conclusions. In two patients with primary hyperaldosteronism, the aldosterone excretion during the night was relatively more elevated than in the day.