Abstract: ObjectiveTo study the expression of suppress or of cytokine signaling 3(SOCS-3)and fatty acid synthase(FAS)mRNA of adipose tissue in obesity and obesity resistant rats induced by high-fat diet.MethodsSeven male Wistar rats were fed with standard diet as control group and 24 rats fed with high-fat diet.After 8 weeks,5 rats as obesity group and 5 rats as obesity resistant group were selected by body weight increment from high-fat diet group.Serum triglyceride,total cholesterol,SOCS-3 and FAS mRNA of epididymal adipose tissues were detected.ResultsSerum triglyce ride (0.982±0.228 mmol/L)and total cholesterol level(2.213±0.364 mmol/L)of obesity group were significantly higher than that of control(0.717±0.153,1.784±0.175 mmol/L,P<0.05),and total cholesterol level was higher than that of obesity resistant group(1.711±0.190 mmol/L,P<0.05).SOCS 23 and FAS mRNA of obesity group was also higher than that of control and obesity resistant group(P<0.05).ConclusionObesity rats and obesity resistant rats induced by highfat diet might be different in gene regulation,and obesity rats show both increased fat synthes is and possible suppression of leptin signaling transduction.