The effect of dietary polyunsaturated fatty acid on insulin sensitivity and lipid metabolism in Otsuka Long-Evans Tokushima Fatty (OLETF) rats

The effects of insulin sensitivity and lipid metabolism of dietary lard, ei cosapentaenoic acid-rich oil (EPA oil) or arachidonic acid oil (AA oil) in Otsuka Long-EvansTokushima Fatty (OLETF) rats were examined. Blood glucose was not different in each group at 30, 60,120 min on an oral glucose tolera nce test. Fasting blood glucose levels were lower in lard and AA oil groups than in controls. Hepatic triglyceride concentration and liver histochemis try revealed that the fat content was higher in the lard group and the AA o il group than in controls. The EPA oil group showed TG levels as high as th e control group. Serum total cholesterol in the EPA oil group was lower, wh ile the level in the AA oil group was higher than in the lard and control g roups. HDL cholesterol was 1.5-fold higher in the AA oil group than in cont rols. Dietary EPA oil or AA oil supplementation showed different effects on lipid metabolism in this model. (C) 2001 Harcourt Publishers Ltd.