CSF renin activity in hypertensive and normotensive patients

CSF samples of hypertensive and normotensive matched groups were assayed and compared for renin activity (RA). The measurements yield low values of RA in both groups without significant difference between them. There was no correlation between the CSF level of RA of each patient and his own concomitant plasma renin activity (PRA). Although the presence of RA in the CSF was confirmed in this study, no direct correlation seems to exist between it values and the elevated blood pressure; therefore, the pathophysiological significance of the renin-angiotensin system in the CSF and its relation to centrally generated hypertension remains questionable.