Lipogenesis in vivo in lean and genetically obese (ob/ob) mice fed on diets with a high fat content
Cawthorne, M.A.; Cornish, S.
International Journal of Obesity 3(1): 83-90
1979
ISSN/ISBN: 0307-0565 PMID: 528121 Document Number: 140747
The effect of change in the fat content of the diet on fatty acid synthesis in vivo was estimated in lean and genetically obese mice, using 3H2O. In lean and obese mice the rate of fatty acid synthesis was higher between 2100 and 2200 h than between 0900 and 1000 h. When lean mice were given a diet high in fat and low in carbohydrate the rate of lipogenesis in adipose tissue and rest of carcass (whole mouse minus liver and adipose tissue) was less than in similar mice given a diet high in carbohydrate and low in fat. In obese mice, the rate of lipogenesis in adipose tissue and rest of carcass was unaffected, but liver fatty acid synthesis was reduced. In lean mice on diets with a constant percentage of carbohydrate and protein, increasing the fat content of the diet and decreasing the proportion of cellulose decreased fatty acid synthesis in liver, adipose tissue and rest of carcass, when the estimations were made during the night-time feeding period. During the day-time, the effect of increasing the fat content of the diet was less marked. In obese mice, dietary fat did not suppress the day-time or the postprandial night-time rate of fatty acid synthesis. It is suggested that the hyperinsulinaemmia in obese mice may be able to overcome the inhibitory effect of dietary fat on fatty acid synthesis.