Effect of dietary fat type on beta-oxidation of brown adipose tissue and Na+ channel density of brain nerve membrane in rats.

Effect of dietary fat type on beta-oxidation of brown adipose tissue and Na+ channel density of brain nerve membrane was studied in rats. Rats were fed an experimental diet containing lard, high oleic safflower oil, safflower oil or linseed oil for 12 weeks. The activities of carnitine palmitoyltransferase and cytochrome oxidase in brown adipose tissue were significantly lower in rats fed the lard diet than in those fed the high-oleic safflower oil diet, safflower oil diet or linseed oil diet. However, the peroxisomal beta-oxidation activity in brown adipose tissue was significantly higher in rats fed the lard diet than in those fed the other diet. The Na+ channel density in brain nerve membrane was not significantly different among the diet groups. These results suggest that intake of the lard diet rich in saturated fatty acids, compared with the vegetable oil diets rich in unsaturated fatty acids decrease mitochondrial beta-oxidation in brown adipose tissue, and that the dietary fat type has a differential effect on mitochondrial and peroxisomal beta-oxidation in brown adipose tissue.