Carbohydrate Storage and Mobilization in the Rat

Abstract

By means of the described procedures the recovery of glycogen from the liver and muscle of fed rats is higher than has been previously reported with a substantial reduction in the coefficient of dispersion. (a) By means of nutritional control, liver glycogen concentrations may be established to a practical precision at any desired level (from 0 to 8% of the tissue, wet weight). (b) Rats on a diet predominating in carbohydrate have a significantly higher liver glycogen concentration at the end of the feeding period than rats on a diet high in protein. However, the reverse is true after the food has been withheld for 24 hours. (c) Maintenance of the animals at a pressure of one-half atmosphere during the fasting period exaggerates the effects of the pre-inanition diets on the liver and muscle glycogen and the blood sugar concentrations. (a) It has been indicated by a regression analysis that a positive physiological relation exists between the blood sugar and the log. value of the liver glycogen concentration in fasted rats and between the liver and muscle glycogen concentrations in both fed and fasted rats. (b) Indications are given of a relationship between the blood sugar and the muscle glycogen concentrations in fasted rats.