Lipogenic capacity and relative contribution of the different tissues and organs to lipid synthesis in male rat.

The rates of 3H2O incorporation into total lipids and fatty acids were measured in vivo in the different organs and tissues of 7-week old male Wistar rats to compare the lipogenic capacity of those organs and tissues and to determine their relative contributions to body lipid synthesis. Our results were the following; (1) liver was the major site of the synthesis of total lipids and fatty acids (37 and 42%, respectively, of body synthesis); (2) white adipose tissues synthesized about 24% of the total lipids; mesenteric adipose tissue alone synthesizing 40% of the fatty acids produced in dissectable white adipose tissues; (3) skin showed low lipid synthesis but played an appreciable role in that synthesis (8% of the total) due to its large contribution to total body weight; (4) other organs (excluding liver) showed low lipid synthesis; however, that of the small intestine was 1-2% of body synthesis; (5) the rest of the carcass (mainly musculature and skeleton) contributed 25% to body lipid synthesis. The putative roles of the different tissues and organs in adipose tissue development have been discussed.