Age-strain interrelations in lipid metabolism of rats.
Various aspects of lipid metabolism were compared in Fisher 344 (F) and Sprague-Dawley (SD) rats aged 2, 6, 12, 18 and 24 months. The analyses included free and total cholesterol of serum and liver, LCAT, hepatic HMG-CoA reductase, cholesterol 7 alpha-hydroxylase, fatty acid synthetase, acetyl CoA carboxylase and cholesterol synthesis from acetate or mevalonate. The body weight of SD rats increases with age whereas that of F rats plateaus at 9-12 months. Liver and aorta cholesterol levels were comparable for the 2 strains. Serum cholesterol varied but was usually lower in F rats. HMG-CoA reductase and cholesterol 7 alpha-hydroxylase activities were not significantly different. Cholesterol synthesis from acetate was significantly higher only in 2-month-old F rats; synthesis from mevalonate was similar at each level. Acetyl CoA carboxylase and fatty acid synthetase activity were generally higher in F rats at every age level. The major difference between F and SD rats is in their pattern of weight gain with age. Differences in lipid metabolism are most marked between the young (2-month) rats.
D000375:Aging; D000818:Animals; D001835:Body Weight; D002784:Cholesterol / Q000096:biosynthesis / Q000378:metabolism*; D002790:Cholesterol 7-alpha-Hydroxylase / Q000378:metabolism; D006903:Hydroxymethylglutaryl CoA Reductases / Q000378:metabolism; D050356:Lipid Metabolism; D008099:Liver / Q000033:anatomy & histology / Q000378:metabolism*; D008297:Male; D007862:Phosphatidylcholine-Sterol O-Acyltransferase / Q000097:blood; D051381:Rats; D013045:Species Specificity
D002784:Cholesterol; D006903:Hydroxymethylglutaryl CoA Reductases; D002790:Cholesterol 7-alpha-Hydroxylase; D007862:Phosphatidylcholine-Sterol O-Acyltransferase