Abstract

BACKGROUND
Resistance to insulin-stimulated glucose uptake is present in the majority of patients with obesity, glucose intolerance, hypertension, dyslipidemia, and coronary artery disease. It is known that values for insulin-stimulated glucose uptake(insulin sensitivity) vary widely within individuals with normal glucose tolerance. We investigated the variations in insulin sensitivity and related factors in the nonobese healthy young men. METHODS: Insulin sensitivity was considered as whole body insulin-stimulated glucose uptake rate(M), determined by euglycemic hyperinsulinemic clamp technique in 44 non-obese healthy young men with normal glucose tolerance. Plasma glucose, insulin, and C-peptide concentrations after a standard oral glucose tolerance test and total cholesterol, triglyceride, and HDL-cholesterol levels were measured after 12-hours fasting. The subjects were divided into four quartiles based on the insulin sensitivity (M) and their clinical and biochemical characteristics were compared. RESULTS: Glucose disposal rates (M-values) were ranged from 4.14 to 11.06 mg/kg/min and distributed normally. The plasma glucose levels were not different between quartiles but plasma insulin levels of quartile 1 were significantly higher than the other three quartiles during oral glucose tolerance test. There was a curvilinear relationship between insulin sensitivity and acute insulin response (Ins[o-30]) to oral glucose challenge. There were negative cnrrelations between insulin sensitivity and BMI, percent ideal body weight, WHR, body fat content, fasting insulin level, insulin response area during OGTT, and fasting serum triglyceride level. HDL-cholesterol concentration was positively correlated with insulin sensitivity. In multiple linear regression analysis, body fat content, fasting insulin, and HDL-cholesterol were independent variables, which were related to the insulin sensitivity. CONCLUSION: There were considerable variations in insulin sensitivity in the nonobese healthy young men with normal glucose tolerance and the related independent factors were body fat content, fasting insulin, and HDL-cholesterol cancentrations.

• Keywords: Insulin resistance;Euglycemic hyperinsulinemic clamp;Insulin sensitivity;HDL-cholesterol;Healthy young men;