The proportion of active (unphosphorylated) branched chain α-ketoacid dehydrogenase was determined in tissues from rats in different metabolic states. Hearts from normal, high-protein, and low-protein fed rats contained about 45% of the enzyme in the active form. Only 10-20% of the enzyme was active in hearts of fasted and diabetic rats. Virtually all of the liver enzyme was in the active form in fed, fasted, diabetic and high-protein fed animals. Protein starved rats, however, exhibited a dramatic decrease in both the % active form and total amount of liver enzyme. Kidneys from normal, fasted, diabetic and high-protein fed rats contained 70-80% of the enzyme in the active form. The % active form of the kidney enzyme decreased in protein starved rats, but less dramatically than in liver. Covalent modification is concluded to be important for in vivo regulation of the branched chain α-ketoacid dehydrogenase complex.
|Original language||English (US)|
|Number of pages||8|
|Journal||Biochemical and Biophysical Research Communications|
|State||Published - Feb 28 1983|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology