Acute effect of atenolol on hemodynamic, plasma renin activity and plasma aldosterone concentration in the once daily oral administration

A new beta-blocking agent, atenolol was studied on the supposition that it was a beta-blocker without any action on central nervous system. Atenolol was orally given to 10 patients with essential hypertension once a day and changes in various parameters were observed through 24 hours. As the results, hypotensive effect was accompanied by marked reduction of heart rate, systemic vascular resistance, plasma renin activity and blood aldosterone level over 24 hours. It was a decrease in systemic vascular resistance that showed best correlation with hypotensive effect.