Effects of L-arginine on metabolism in fructose-fed rats

Objective:To study whether L-arginine prevents elevated blood pressure and improves insulin resistance in fructose-fed rats and its effect on serum TNF-α.Methods:Adaptively fed for one week,male Sprague-Dawley rats aged 5~6 weeks were divided into four groups:fructose group,fed with 60 % high fructose diet;control group,fed with regular-diet with the same calories ;fructose +L-arginine(L-Arg)group,fed with high fructose-diet and 2.25 %L-arginine solution;and L-Arg group,fed with regular diet and 2.25 %L-arginine solution.Blood pressure was measured weekly;serum insulin and glucose were assayed biweekly.Six weeks later,all the rats were sacrificed and their blood samples were collected;the concentrations of fasting serum insulin(FINS),triglyceride(TG)and TNF-α were determined.Results:The insulin,systolic blood pressure,triglyceride content of fluctose group significantly increased(P0.05 all),compared with control group.Serum insulin and triglyceride levels in fluctose+L-Arg group were significantly lower than those in fluctose group(P0.05),and no hypertension appeared in fluctose+L-Arg group.Serum TNF-α content decreased(P0.05)in fluctose+L-Arg group compared with fluctose group.Conclusion:High fructose feeding results in insulin resistance accompanied by elevated blood pressure,TNF-α levels and dyslipidemia.L-Arginine can prevent hypertension and improve insulin resistance and dyslipidemia.