ABSTRACT
Sophocarpine ( SC ) , an alkaloid extracted from sophora alope -curoides L. , was found to have a rapid and significant hypotensive action both in anesthetized dogs and in conscious renal hypertensive rats. On superior cervical ganglia and nictitating membrane preparation ,SC 15mg, administered via lingual artery, briefly relaxes the rigid contraction of nictitating membrane caused by continuous stimulation of sympathetic preganglionic fibers. SC 50, 100, 200?g/kg reduced the vascular resistance index 13.1 ?1.6%, 20.5?4.6%, 27.8?4.1% respectively when perfused into the femoral artery .Measurement of the changes of hemodynamics with constant voltage transthoracic admittance plethysmograph in 5 intact anesthetized dogs showed that SC iv 25mg/ kg enhenced the index of myocardial contractility 18% and heart beat index 40%, shortened Q -Y interval 37%.These results suggest that hypotensive action of SC should be realized by both relaxing the peripheral vascular smooth muscules and blocking the transmission of impulse through the sympathetic ganglia.