Effects of 3'-angeloyloxy-4'-acetoxy-3',4'-dihydroseselin on cardiohemodynamics in anesthetized dogs

Cardiohemodynamic effects of 3'-angeloyloxy-4'-acetoxy-3',4'-dihydroseselin (Pd-Ia) isolated from the Chinese medicinal plant Peucedanum praeruptorum Dunn were compared with those of diltiazem (Dil) in anesthetized open-chest dogs. Pd-Ia 3 mg.kg-1 increased coronary blood flow from 25 +/- 11 to 58 +/- 16 ml.min-1 (n = 7, P < 0.01) and decreased mean aortic pressure (MAP) from 13 +/- 2 to 8 +/- 1 kPa (P < 0.01), rate pressure product (RPP) from 1.9 +/- 0.5 to 1.3 +/- 0.3 MPa.bpm (P < 0.05), +dp/dtmax from 246 +/- 56 to 160 +/- 36 kPa.s-1 (P < 0.01) and systemic vascular resistance from 19 +/- 4 to 12 +/- 7 Pa.ml-1.min-1 (P < 0.05), together with an increase in HR. Dil showed effects similar to those of Pd-Ia except for a marked decrease in HR. The effects of Pd-Ia on MAP and RPP were approximately one-tenth as potent as those of Dil. The results demonstrated that Pd-Ia was a Ca2+ channel blocker.