[Plasma renin activity, arterial blood pressure and response to beta-adrenergic blockade: a non-demostrated...

Nineteen patients have been treated with timolol maleate (a non selective beta-blocking) and the decrease of their blood arterial pressure was correlated with the suppression of renine secretion. The patients which controlled their arterial pressure (63%) as well as those who did not (37%) showed a significative decrease of the plasmatic renine. The patients were diagnosed of essential hypertension, with normal renal function and formed an homogenous group. The sodium intake was similar in all of them. The results showed that although the beta-blocking can act in hypertensive patients through the suppression of the renine angiotensine system, this is not the only maintenance factor of the arterial pressure, nor its only way of action. A relevant point to be stressed in the possibility of ARP stimulation by walking, in spite of the beta-blocking, which means that this is not a total blocking or that there are other factors regulating the ARP secretion, and that act together with the autonomous nervous system.