Antihypertensive Effect of Kolaviron, a Bioflavonoid From Garcinia kola, in L-NAME Induced Hypertension in Rats

Abstract

The antihypertensive effect of Kolaviron (KV) has been demonstrated in ethanol- and sucrose-model of hypertension in our previous studies. However, there remains a need to further confirm and validate this effect in other models of hypertension. This study was devised to appraise the antihypertensive action of KV in N(G)-nitro-L-arginine methyl ester (L-NAME) induced experimental format of hypertension. Thirty-six (36) male Wistar rats were divided into 6 groups of 6 animals each. Group I represents the control group while Group II animals received L-NAME 40 mg/kg only. Groups III to V animals received L-NAME 40 mg/kg and 50, 100, and 200 mg/kg KV, respectively. Group VI animals received L-NAME 40 mg/kg and 0.14 mg/kg Lisinopril (LIS). Treatment was done orally for 28 days after which blood pressure was determined via the invasive method. After this, vital organs and blood were retrieved for analysis. KV and LIS elicited significant contraction ( P < .01-.001) in blood pressure producing up to 27%, 24%, and 22% reduction in systolic blood pressure, diastolic blood pressure, and mean arterial pressure, respectively. In addition, KV elicited a notable rise ( P < .05-.001) in catalase, reduced glutathione, and superoxide dismutase in the blood and vital organs. Results from this study further demonstrate and confirm that KV possesses notable blood pressure-lowering effect possibly through its well-documented antioxidant effect. Additional studies are advocated to validate the results from this study and determine the precise mechanism for the antihypertensive action of KV.