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 a nd Na+ channel density of brain nerve membrane was studied in rats. Ra ts were fed an experimental diet containing lard, high oleic safflower oil, safflower oil or linseed oil for 12 weeks. The activities of car nitine palmitoyltransferase and cytochrome oxidase in brown adipose ti ssue were significantly lower in rats fed the lard diet than in those fed the high-oleic safflower oil diet, safflower oil diet or linseed o il diet. However, the peroxisomal beta-oxidation activity in brown adi pose tissue was significantly higher in rats fed the lard diet than in those fed the other diet. The Na+ channel density in brain nerve memb rane was not significantly different among the diet groups. These resu lts suggest that intake of the lard diet rich in saturated fatty acids , compared with the vegetable oil diets rich in unsaturated fatty acid s decrease mitochondrial beta-oxidation in brown adipose tissue, and t hat the dietary fat type has a differential effect on mitochondrial an d peroxisomal beta-oxidation in brown adipose tissue.