抄録
In 19 vagotomized open-chest dogs with sodium pentobarbital anesthesia, hemodynamic effects were evaluated following injection of angiotensin into either vertebral artery using a fine catheter tied into place. Doses of 5ng/Kg produced an increase in both right ventricular stroke volume and the maximum rate of right ventricular pressure rise, without an effect on the left ventricle, mean pulmonary artery pressure (MPAP) mean systemic arterial pressure (MAP) or heart rate (HR). Doses of 10ng/Kg caused an increase in both right and left ventricular stroke volume and dp/dt without an effect on MAP, MPAP, or HR. Doses from 15 to 50ng/Kg raised arterial pressure, which was accompanied by an augmented HR, stroke volume and dp/dt of both ventricles. These effects, however, could not be reproduced by similar intravenous or intracarotid artery doses which provided an equipressor response. These results may suggest that the central nervous system activity of angiotensin operates by stimulation of sympathetic, predominantly beta adrenergic sites.
