To investigate the influence of saturated fats, α-linolenic acid, EPA and DHA on the lipid hydroperoxide concentration and fatty acid composition in liver microsomes and in plasma lipid of rabbits, the animals were fed on the perilla oil rich α-linolenic acid or sardine oil rich EPA and DHA diet for four weeks Were examined. The fatty acid composition of plasma lipid and liver microsomes of rabbits fed on the perilla oil diet was an accumulation of arachidonic acid(AA) 20:4 n-6, eicosapentaenoic acid(EPA) 20:5 n-3, and docosahexaenoic acid(DHA) 22:6 n-3, The fatty acid composition of plasma lipid and liver microsomes of rabbits fed on the sardine oil was an accumulation of α-linolenic acid(LNA) 18:3 n-3, and arachidonic acid(AA) 20:4. The p/s ratio of rabbits fed on the perilla oil diet changed from 7.4 to 2.27 for plasma lipid and 2.47 for liver microsomes. The concentration of lipid hydroperoxide was 3.48 nmol MDA/ml and 4.35 nmol MDA/ml for plasma lipid and liver microsomes, respectively, in perilla oil diet. The lipid hydroperoxide liver was 4.22 nmol MDA/ml and 67 nmol MDA/ml for plasma lipid and liver microsornes in sardine oil diet.
Effect of perilla oil on the fatty acid composition, ACAT and HMG-CoA reductase in the liver microsomes, or cholesterol and protein in serum of rabbit were examined. 1. The content of total protein in serum was almost same amount of both groups, but α1-globulin and r-globuline were incresed or β-globulin was decresed compared with control. 2. The content of high density lipoprotein incresed, and the content of low density lipoprotein decresed in lipoprotein. 3. Total cholesterol and triglyceride were decresed, and the content of phospholipid was incresed. 4. Perilla oil did not effect for changing blood glucose and Na+, K+ electrolytes. 5. Perilla oil did not effect for changing serum GOT and GPT in rabbit. 6. The activity of ACAT decresed and the activity of HMG-CoA reductase incresed. The activity of ACAT and HMG-CoA reductase in liver microsomes were reciprocal. 7. There were arachidonic acid 20:4, eicosapentaenoic acid 20:5, and docosahexaenoic acid 22:6 in the liver microsomes of rabbits. These highly polyunsaturated fatty acids were convented from linolenic acid 18:3 n-3.