Abstract:Vascular resistance and blood flow were measured in anesthetlized dogs with roller pump and electromagnetic flowmeter. Intravenous or intraarterial injection of CsA, a component isolated from cultured Cordyceps sinensis(Berk)Sacc inoreased coronary artery blood flow and reduced coronary, cerebral and peripheral vascular resistance. A fall of arterial blood pressure was observed. Vasodilatation of CsA did not prove to be related to α,β_2and H receptor but was antagonized by atropine. The main mechanism of vasodilatation may be that CsA stimulates M receptor and adenosine, a composition of CsA, relaxes the vascular smooth muscle directly.