Carbohydrate metabolism control

Magnesium plays an important role in the transmission of nerve impulses. It is also important in the activity of many enzyme reactions, for example carbohydrate metabolism. Magnesium sulfate is used as replacement therapy in hypomagnesemia Magnesium sulfate (MgS04) is used in die prevention and control of seizures in obstetric patients with pregnancy-induced hypertension (PIH, also referred to as eclampsia and preeclampsia). It may also be added to TPN mixtures. 

Hormones have a profound effect on carbohydrate metabolism. Great interest has been aroused by reports of hormonal control of hexokinase activity by specific proteins in animal tissues.99- 100 Hexokinase action is the rate-limiting step in the uptake of D-glucose by muscle. Hexokinase is inhibited in diabetic muscle, but the inhibition can be partially reversed by insulin. A protein fraction from the anterior pituitary gland will inhibit the hexokinase of extracts of brain and muscle, and the effect of this... 

In all organisms, carbohydrate metabolism is subject to complex regulatory mechanisms involving hormones, metabolites, and coenzymes. The scheme shown here (still a simplified one) applies to the liver, which has central functions in carbohydrate metabolism (see p. 306). Some of the control mechanisms shown here are not effective in other tissues. 

Metabolic Control Analysis Has Been Applied to Carbohydrate Metabolism, with Surprising Results... 

An interesting suggestion for the regulation of carbohydrate metabolism by FDPase is that of Newsholme and Crabtree (79), who have proposed that it can act as a modulator of the control of phosphofructokinase by AMP in muscle. A similar suggestion for regulation of carbohydrate metabolism in liver has been advanced by Williamson and co-workers (114). 

Biochemistry resulted from the early elucidation of the pathway of enzymatic conversion of glucose to ethanol by yeasts and its relation to carbohydrate metabolism in animals. The word enzyme means "in yeast," and the earlier word ferment has an obvious connection. Partly because of the importance of wine and related products and partly because yeasts are relatively easily studied, yeasts and fermentation were important in early scientific development and still figure widely in studies of biochemical mechanisms, genetic control, cell characteristics, etc. Fermentation yeast was the first eukaryote to have its genome elucidated. 

The clear distinction between the glycoprotein and glycolipid sialyltransferases suggests that the extent of sialylation of the two classes of complex carbohydrates in vivo may be under different metabolic controls. This notion is supported by the observation that the developmental profiles of the glycoprotein and glycolipid sialyltransferases are distinctly different. 

Morphological changes were also observed on callus of Pinus laricio cultured for 4 weeks with HS extracted from forest soil under Abies alba and Fagus sylvatica plantation or the hormones 2,4D, IAA, and 6BAP (Muscolo et al., 2005).The results showed that both high- and low-molecular-weight humic fractions inhibited callus growth compared to the control and affected the enzymes involved in carbohydrate metabolism. 

Related topics Membrane lipids (El) Cholesterol (K5) Membrane protein and Nerve (N3) carbohydrate (E2) Control of glycogen metabolism 07)... 

Because phenothiazines affect carbohydrate metabolism, they can interfere with the control of blood glucose in diabetes mellitus (445,623). 

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