Glycogen, function

Glycoconjugate, 991 Glycogen, function of, 1001 structure of, 1001 Glycol, 234, 662 Glycolic acid, pKa of, 756 structure of, 753 Glycolipid, 991... 

M. D. Grmek, First steps in Claude Bernard s discovery of the glycogenic function of the liver , J. Hist. Biol., 1968,1, 141-154. 

Starch is the principal food reserve of plants, glycogen functions as a carbohydrate reserve for animals, and cellulose serves as structural material in plants. 

The roles of liver and skeletal muscle glycogen, however, differ. Liver glycogen functions as a reservoir of glucose which is released to maintain the concentration of glucose in the blood circulation from which other tissues, e.g. brain, draw their supply of glucose. Liver glycogen levels... 

John.son, L. N., and Barford, D., 1993. The effects of pho.sphorylation on the. structure and function of proteins. Annual Review of Biophysics and Biomolecular Structure 22 199-232. A review of protein pho.sphorylation and its role in regrdation of enzymatic activity, with particular empha.sis on glycogen pho.sphoryla.se. 

Figure 6. Glycogen content in the vastus lateralis muscle as a function of cycling time at 75-80% of maximal oxygen uptake (VO2 max). Data points are mean values from 10 subjects. For each subject, exercise was performed repeatedly in periods of 15 min separated by 15 min rest periods. At the point of exhaustion and muscle fatigue, muscle glycogen stores were depleted. From Bergstrom and Hultman (1967) with permission from the publisher.

Potassium is the second most abundant cation in the body and is found primarily in the intracellular fluid. Potassium has many important physiologic functions, including regulation of cell membrane electrical action potential (especially in the myocardium), muscular function, cellular metabolism, and glycogen and protein synthesis. Potassium in PN can be provided as chloride, acetate, and phosphate salts. One millimole of potassium phosphate provides 1.47 mEq of elemental potassium. Generally, the concentration of potassium in peripheral PN (PPN) admixtures should not exceed 80 mEq/L (80 mmol/L). While it is safer to also stick to the 80 mEq/L (80 mmol/L) limit for administration through a central vein, the maximum recommended potassium concentration for infusion via a central vein is 150 mEq/L (150 mmol/L).14 Patients with abnormal potassium losses (e.g., loop or thiazide diuretic therapy) may have higher requirements, and patients with renal failure may require potassium restriction. 

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