The effects of unripe grape extract on systemic blood pressure and serum levels of superoxide dismutase, malondialdehyde and nitric oxide in rat

BACKGROUNDS: The new lifestyle increases the incidence of hypertension. In Iranian folk medicine, it is believed that Verjuice obtained by unripe grape (Vitis vinifera) could control blood pressure. We tested the effects of unripe grape extract (UGE) in blood pressure alteration, serum antioxidant level and aorta endothelial permeability in rats. MATERIALS AND METHODS: Four groups of rats were treated daily by placebo and three different doses of UGE (50, 150 and 300 mg/kg/day). Four weeks later, the animals were anesthetized and catheterized. The direct mean arterial, systolic and diastolic pressures (MAP, SP and DP) were recorded. The endothelial permeability was determined and the serum levels of superoxide dismutase (SOD), malonaldialdehyde (MDA) and nitrite were measured. RESULTS: High dose of UGE increased MAP and SP significantly (P < 0.05) when compared with the control group. Decrease of MDA and increase of SOD and nitrite also were detected statistically in animals treated with high dose of UGE (P < 0.05). No difference in aorta endothelial permeability was observed between the groups. CONCLUSION: The effect of UGE on blood pressure was dose dependent. High dose of UGE increased MAP and SP although its antioxidant activity was significantly high. Such observation mechanisms need to be defined.