Reduction of lipogenic enzymes by shellfish triglycerides in rat liver.

When rats were fed for 2 weeks on 3% fat diets containing 0.5 or 1%corbicula (Corbicula japonica PRIME), clam (Tapes japonica) or oyster (Callocorchina) triglycerides, serum and liver triglyceride levels were significantly lowered. The activities of hepatic glucose-6-phosphate dehydrogenase, malic enzyme and acetyl-CoA carboxylase were markedly reduced in the rats. Cholesterol synthesis by liver slices was also reduced. The results of immunochemical titrations and Ouchterlony double-diffusion analysis indicated that the decreases in the activities of acetyl-CoA carboxylase and glucose-6-phosphate dehydrogenase were due to decreases in the enzyme quantities. The shellfish triglycerides include a high percentage of long chain and polyunsaturated fatty acids, which are common to and characteristic of the three kinds of shellfish. They would be effective components in these observations.