Regulation of Intralipid-Induced Dyslipidemia- Hyperglycemia by Exogenous L-Arginine in Experimental Animals

Aim: This study was undertaken to investigate the possible beneficial effects of exogenous L-arginine in ameliorating or regulating dyslipidemia and hyperglycemia induced in experimental animals. Methods: Male Sprauge-Dawley rats were rendered dyslipidemic and hyperglycemic by intravenous injection of 20% intralipid (8.5 ml/kg b.w.) daily for three weeks. Plasma levels of glucose, total cholesterol (TC), lowdensity lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), very low-density lipoprotein cholesterol (VLDL-C), triglycerides (TG) and free fatty acids (FFA) as well as liver content of TC and TG, were measured in rats that were intravenously injected with 20% intralipid for 21 days in the presence and absence of exogenous L-arginine. Results: After intralipid administration, plasma levels of glucose, TC, LDL-C, VLDL-C, TG as well as liver content of TC and TG were significantly increased. On the other hand, plasma levels of HDL-C were significantly decreased. However, the intraperitoneal injection of L-arginine (500 mg/kg b.w.) for 14 days either before or after intralipid administration maintained all parameters studied at or near control values. Conclusions: These results provide evidence of the beneficial effects of exogenously administered L-arginine in normalizing experimental dyslipidemia and hyperglycemia in rats. These beneficial effects might be attributed to its direct NO-dependent pathway.