Evidence is presented in support of a pathway in skeletal muscle of glyconeogenesis (glycogen biosynthesis de novo) from L-glutamate and related amino acids involving the enzyme phosphoenolpyruvate carboxykinase (PEP CK). In the rat hemidiaphragm in vitro, not only did L-[U-14C]glutamate exert a glycogen-sparing action, but14C-label was incorporated into glycogen. The incorporation is thought not to be simply via label randomization and was decreased by factors that increased glycolysis or pyruvate oxidation. 3-Mercaptopicolinate and amino-oxyacetate, specific inhibitors of PEP CK and aminotransferase-type enzymes, respectively, decreased14C-incorporation from L-[U-14C]glutamate into glycogen. No quantitative determination of apparent glyconeogenic flux was made, and it remains to be established whether glyconeogenesis via PEP CK and/or via PEP CK coupled with 'malic' enzyme (or pyruvate carboxylase) is functionally important in skeletal muscle.
Research Article| February 01 1981
A putative pathway of glyconeogenesis in skeletal muscle
Bhanu R. Odedra;
Bhanu R. Odedra
1Department of Biochemistry, Charing Cross Hospital Medical School, Fulham Palace Road, London W6 8RF, U.K.
*Clinical Nutrition and Metabolism Unit, London School of Hygiene and Tropical Medicine, Hospital for Tropical Diseases, 4 St. Pancras Way, London NW1 2PE, U.K.
Search for other works by this author on:
- Views Icon Views
- Share Icon Share
- Cite Icon Cite
Bhanu R. Odedra, T. Norman Palmer; A putative pathway of glyconeogenesis in skeletal muscle. Biosci Rep 1 February 1981; 1 (2): 157–165. doi: https://doi.org/10.1007/BF01117013
Download citation file: