Urinary excretion of renin and angiotensinogen in nephrotic rats.

Puromycin aminonucleoside (PA)-nephrotic rats have a high plasma renin activity (PRA) and low angiotensinogen levels. We measured proteinuria, urine renin, and urine angiotensinogen daily, for 11 days after PA injection. Proteinuria and urine angiotensinogen were evident on day 5, and urine renin on day 6. Peak levels of urine renin and angiotensinogen were attained on day 8. These data suggest that angiotensinogen urine excretion may contribute to its low plasma levels, and urine renin loss may limit a further increase in PRA.