Study on the Effect of a High Fat Diet on Diaphragm and Liver Glycogen and Glycerides in the Rat

This is the authors' abstract. We don't add key points for this paper.

The present work was undertaken to study the effect of nutritional obesity induced by a high fat diet on the consumption of glycogen and glycerides in rat liver and diaphragm. Groups of rats were fed for five weeks from weaning either a fat-rich-carbohydrate (CHO)-poor diet, or a CHO-rich-fat-poor diet. Basal plasma glucose and free fatty acids (FFA) were significantly increased in the animals adapted to the fat-rich diet. Half of the rats were submitted to a 48-h fast. After fast, basal plasma glucose and immunoreactive insulin (IRI) fell significantly, whereas plasma FFA levels were higher than in the group fed the CHO-rich-fat-poor diet. In the liver, glycogen concentration fell in both groups after fast, with a glycogen breakdown of 1930 +/- 244 mumole glycogen glucose/liver in the fat-fed group vs 4636 +/- 216 mumole/liver in the CHO-fed group. Glycerides fell by 750 +/- 68 mumole glyceride glycerol/liver in the fat-fed rats while remaining unchanged (increased by 82 +/- 57 mumole/liver) in the CHO-fed group. In the diaphragm glycogen concentration also fell in both groups, with a glycogen breakdown of 6.0 +/- 0.3 mumole glycogen glucose/g wet tissue in the fat-fed rats vs 15.2 +/- 1.4 mumole/g wet tissue in the CHO-fed animals. Glycerides fell by 23.1 +/- 4.0 mumole/g wet diaphragm in the CHO-fed animals. The lower breakdown of glycogen in both liver and diaphragm of fat-fed rats demonstrates a decreased utilization of glycogen during fast, with energy consumption originating in larger part from triglycerides.(ABSTRACT TRUNCATED AT 250 WORDS)