Relations entre l'ingestion d'acides gras à chaîne moyenne par la ratte et la lipogénèse du jeune raton avant le sevrage

Abstract

In the rat, prolonged intake of a large quantity of lauric acid (C12:0) before and during pregnancy had no effect on the amount of lipids present in adipose stores at the time of parturition. However, this medium chain fatty acid was intensely esterified in the triglycerides of the maternal adipose tissues. As compared to a diet rich in long chain fatty acids, the intake of lauric acid during lactation considerably modified mammary gland fatty acid secretion. Lauric acid was esterified in very high proportions (about 35 p. 100 of the total fatty acids) in milk triglycerides, thus considerably increasing its saturated fatty acid content (about 80 p. 100 of the total fatty acids). In these nutritional conditions, the mammary gland could not efficiently regulate the qualitative aspects of fatty acid secretion. However, these large modifications of the milk triglyceride fraction did not change the weight of the pups at weaning and had no effect on their body composition. This would indicate that the growth of the lipid compartment was unchanged. The weight of the liver, its total lipid content and the distributions between neutral lipids and phospholipids were identical to those of the controls. A large amount of the lauric acid ingested by the mother was transferred to the pup in the milk before weaning. A large quantity was found in the body triglycerides (30 p.100 of the total fatty acids) and in neutral liver lipids. It was not incorporated directly into hepatic phospholipids.