Cardiovascular Activity of Labdane Diterpenes fromAndrographis paniculatain Isolated Rat Hearts

Abstract

The dichloromethane (DCM) extract ofAndrographis paniculataNees was tested for cardiovascular activity. The extract significantly reduced coronary perfusion pressure by up to24.5±3.0 mm Hg at a 3 mg dose and also reduced heart rate by up to49.5±11.4 beats/minute at this dose. Five labdane diterpenes, 14-deoxy-12-hydroxyandrographolide (1), 14-deoxy-11,12-didehydroandrographolide (2), 14-deoxyandrographolide (3), andrographolide (4), and neoandrographolide (5), were isolated from the aerial parts of this medicinal plant. Bioassay-guided studies using animal model showed that compounds, (2) and (3) were responsible for the coronary vasodilatation. This study also showed that andrographolide (4), the major labdane diterpene in this plant, has minimal effects on the heart.