Calcium channel blockade in vascular smooth muscle cells: major hypotensive mechanism of S-petasin, a hypotensive sesquiterpene from Petasites formosanus - Wang,G.J.; Shum,A.YC.; Lin,Y.L.; Liao,J.F.; Wu,X.C.; Ren,J.; Chen,C.F. (Journal of Pharmacology and Experimental Therapeutics, 2001)