Active and inactive renin and kidney function in young subjects with different predisposition to develop essential hypertension.

Renal and cardiac function were measured in 65 offspring of hypertensive parents (OHP) and in 56 offspring of normotensive parents (ONP). In two additional groups of 24 OHP and 42 ONP plasma renin activity (PRA) and plasma active (PRAC), inactive (PRIC) and total (PRTC) concentration were measured. OHP had significantly higher renal plasma flow (p less than 0.01), glomerular filtration rate (p less than 0.02) and 24-hour urinary output than ONP, while PRA was lower (p less than 0.01). The measurements of the different forms of renin gave the following results: PRIC and PRTC were lower in OHP than in ONP, but the only statistically significant difference concerns PRIC (p less than 0.025). A possible interpretation of these findings is that a primary increased tubular ion and water reabsorption might be the cause of the kidney function pattern seen in OHP.