Disturbed relationship of plasma-renin to blood-pressure in hypertension.

Abstract A significant inverse relationship is reported in 78 normotensive individuals between blood-pressure and both plasma-renin-activity (P.R.A.) and plasma-renin concentration (P.R.C.). A similar relationship was not found in 76 hypertensive individuals. Use of the linear regression line of log P.R.C. v . mean blood-pressure for the 78 normotensive individuals revealed that 55% of hypertensive subjects had high P.R.C. (beyond 95% confidence limits) while none had low P.R.C. These data suggest that a negative feedback normally exists between blood-pressure and renin release, and that this mechanism operates imperfectly in a large proportion of individuals with mild hypertension, resulting in an inappropriately large release of renin for the level of blood-pressure. While a correlation between sodium excretion and blood-pressure was found, the relationship between renin and blood-pressure seems independent of the amount of sodium intake. An awareness of these relationships necessitates a reappraisal of the role of renin in hypertension.