Adenylate deaminase activity in the rat. Effect of 24 hours of fasting.

The adenylate deaminase activity of liver, kidneys, brain, striated muscle, stomach, intestine, skin and adipose tissue of fed and 24 hours fasted rats has been studied. The level of activity of the enzyme in muscle is at least an order of magnitude higher than in other organs. Fasting induced a significant increase in the muscle adenylate deaminase activity, while in kidneys, skin, small intestine, liver and adipose tissue, significant decreases were observed and practically no changes were found in brain and stomach. The possible incidence of these changes upon the overall alpha-amino nitrogen economy of the fasted animals is discussed.