Evaluation of insulin resistance and associated factors in male OLETF rats

Objective To investigate the insulin resistance status in male OLETF rats and its relationship to some associated factors. Methods 10 male OLETF rats and 10 male LETO rats (as control) of 14 weeks old were selected. The amount of daily food intake, body weight, and visceral fat content were recorded. Urine was collected for measuring Alb/Cr and Cp/Cr indexes, and fasting blood sample for lipid profile. Skeletal muscle was fetched after sacrificed for the analysis of fatty acid composition. Hyperinsulinemia clamp was used to evaluate the insulin resistant status of the rats.Results Compared with LOET rats, the characteristics of OLETF rats were: ①more daily food intake; ② higher body weight; ③ higher serum TG and CH levels; ④ higher Cp/Cr index; ⑤ higher blood glucose le vels in OGTT except fasting ones; ⑥ lower GIR; ⑦ higher n 6 PUFA and lower n 3 PUFA, with similar total PUFA composition.Conclusion Despite of NGT, insulin resistance had already existed in 14 weeks old male OLETF rats simultaneously manifesting higher body weight, high visceral fat deposition and elevated TG. CH levels associaled with significant change of fatty acid composition in the skeletal musle