Investigation of resveratrol on endothelial function in alloxan-induced diabetic rabbits

Diabetes mellitus is a metabolic disorder and is characterized by vascular complications which have become more prevalent in both developed and developing societies. Also diabetes mellitus has been regarded as one of the major factors contributing to the risk of coronary heart disease and atherosclerosis. Epidemiological studies demonstrate that average consumption of red wine causes a prominent decrease in the mortality rate of cardiovascular diseases including diabetes mellitus. As one of the bioactive components of red wine, resveratrol attenuates oxidative stress and augments anti-oxidant potential by increasing nitric oxide formation and vascular endothelial reactivity. However the effects of resveratrol on development of diabetes mellitus and its vascular complications have not been investigated yet. The present study investigates the effects of resveratrole on the acetylcholinic contraction and phenylephrinic relaxation on control rabbits, which were made diabetic by alloxane (100 mg/kg), diabetic rabbits which took high dose (50 mg/kg) resveratrole simultaneously and rabbits which drank high dose resveratrole after taking a low dose (5 mg/kg). Also the alterations in contraction and relaxation functions pursued by 30-minute-long indomethacine and L-Nitro arginin incubations are recorded. Moreover the following related to experiment groups are registered: blood glucose levels, weights preceding the study, amounts of drinking water with and without resveratrole. As indicated by in-vitro studies and graphics, diabetic rabbits that consumed resveratrol have become more sensitive to acetylcholine and less sensitive to phenylephrine when compared to non-diabetic rabbits which took resveratrol simultaneously. These findings confirm that resveratrol causes relaxation of vascular system and inhibits its contraction. The same experimental studies also point out that indomethacin acts synergistically with resveratrol whereas L-Nitro-Arginine inhibits its relaxing effects on vascular system.