[Effects of postural changes and volume depletion on renin-angiotensin system (author's transl)].

The effects of orthostatism and furosemide tests on different parameters of renin-angiotensin system have been studied in 14 normal human subjects. Both tests produced a significant increase in plasma renin activity and plasma renin concentration. Plasma substrate concentration was slightly, but significantly, increased on the furosemide test. Plasma aldosterone rose in both tests, while aldosterone urinary excretion decreased after orthostatism and increased after furosemide.