Pharmacodynamic study on acute hypotensive activities of Carissa carandas extract in normal rats

This study aims to evaluate the effect of Carissa carandas extract on cardiovascular function of normal rats. Intravenous bolus injection of this extract in the doses of 5 mg kg(-1)_-45 mg kg(-1), produced dose dependent reduction in arterial blood pressure (p<0.001). The 45mg/kg dose caused a 50.75% ± 2.71 decrease in MABP which was highly significant with P value < 0.0005 when compared with its controls. Significant reduction in heart rate frequency was observed after CC injection at a dose of 45 mg kg-1 (p<0.001). The results were comparable with Acetylcholine 10(-4) M. The receptor activity performed for which Atropine 10(-4)M was administered I.V. and then the extract (45mg/kg) was administered. A highly Non Significant fall in Mean Arterial Blood pressure was observed 1.51% ± 0.22 (P>0.05). It was concluded that the Carissa carandas Ethanol extract possess potent acute hypotensive effect in normal rats. It stimulates the muscarinic receptors located on the endothelial cells of the vasculature. This stimulation results in the release of endothelial-derived relaxing factors (EDRFs) or nitric oxide that diffuses to vasculature smooth muscles and causes their relaxation.