Cardiovascular effects of the alkaloid hippadine on the isolated perfused rat heart.

Crinum macowaniihas been used extensively in traditional medicines for treatment of various il lnesses such as oedema and 'heart disease'. Previous studies of the crude bulb extracts on Langendorff perfused isolated rat hearts indicated a positive inotropic effect. The aim of this study was to isolate and characterize compound(s) from C. macowa- nii with cardiovascular effects similar to that observed with the crude e xtracts of the plant. The methanol extract of dried bulbs was extracted for alkaloids, and structural elucidation of the isolated alkaloid identified it as hippadine. The card i- ovascular effects of hippadine was evaluated in vitro in isolated perfused rat he arts using the double sided working heart system. Perfusion with 0.5 μg/ml and 5.0 μg/ml hippadine in Krebs-Hanseleit buffer led to significant decreases in coronary flow, aortic output, cardiac output, systolic pressure, and heart rate, accompanied by increases in diastolic pre s- sure. Hippadine exhibited a negative chronotr opic and inotropic effect on the isolated rat heart and is responsible either partly or fully for the cardiovascular effects of C. macowanii.