Anti-Hypertensive and Anti-Oxidative Effect of Methanolic Extract of Vernonia Amygdalina (VA) in Tissue Samples of NaCL Induced Hypertensive Male Wistar Rats

Abstract

Vernonia amygdalina (VA) is a medicinal plant cultivated in Nigeria and widely used as vegetables and in folk medicine in the treatment and prevention of many diseases like diabetes and hypertension. The aim of the study was to evaluate the antihypertensive and antioxidative effect of methanolic extract of VA in 8% NaCl induced hypertensive male wistar rats. Forty wistar rats (120-160) g were assigned to 5 groups of eight rats each. Group 1,2,3,4 and 5 constitute the normal, hypertensive group, VA (200mg/kg bwt) group, VA (400mg/kg bwt) group and reference drug (lisinopril, 30mg/kg/2mls/day) group respectively. Group 3 and 4 were given the extract by gastric intubation for 4weeks after induction while group 5 was given the reference drug. All groups except group 1 were induced with 8% NaCl for 0- 4weeks before treatment with VA and reference drug for 4-8weeks. VA significantly (p<0.05) reduced blood pressure, heart rate and blood volume after 4 weeks induction in group 3 and 4 in a dose dependent manner. The tissue lipid peroxidation product (MDA) was significantly(p<0.05) reduced and the tissue antioxidant enzymes activities (SOD, CAT and GST) were significantly (p<0.05) increased in VA extract group but not in lisinopril group. The result of the study suggests that VA possess antihypertensive effect against NaCl-induced hypertension with additional antioxidative properties that may help in ameroliating the effect of oxidative stress in hypertensive condition.