Violations of the intermediate metabolism of carbohydrates

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Causes of disorders of intermediate metabolism of carbohydrates can be:

1. Hypoxia caused by circulatory failure, respiratory and other. Developing a deficiency of oxygen cell metabolism switches from aerobic to anaerobic type, in which the main source of energy becomes anaerobic glycolysis. The decay of glucose in these circumstances an excess of lactic and pyruvic acids. Lactic acid enhances tissue oxyhemoglobin dissociation and expansion of the coronary vessels, compensating thus hypoxia phenomena. In normal tissues of lactic acid, which is glycolysis (e.g., muscle), blood enters the liver (Cori cycle), where it is converted by the enzyme lactate to pyruvate. Pyruvate is partially oxidized in the liver and is partially converted to glucose (gluconeogenesis). Thus, lactate returned to metabolic pool of carbohydrates. Prolonged existence of excess lactic acid in the tissues leads to deficiency of substrate oxidation - glucose, which causes a further decrease in the efficiency of ATP synthesis. Macroergs deficiency underlies disorders transmembrane ion transport membrane and increase permeability. Ultimately, this leads to significant structural and functional damage in tissues until cell death.

2. Violations of the liver. The lactic acid hepatocytes part resynthesis normal glucose and glycogen. If it affects the liver, this process is disrupted, lactic acid goes into the blood, develops acidosis.

3. Hypovitaminosis B1. Vitamin B1 (thiamine) as a result of phosphorylation process is converted into cocarboxylase - prosthetic group of some enzymes of carbohydrate metabolism. When failure occurs deficiency of vitamin B1 cocarboxylase, which leads to suppression of the synthesis of acetyl-CoA from pyruvic acid, and the latter is accumulated partially converted into lactic acid, the content of which in this connection is increased. pyruvic acid oxidation braking reduces the synthesis of acetylcholine, which causes violation of transmission of nerve impulses. With increasing concentration of pyruvic acid by 2-3 times compared with the norm there are violations of sensitivity, neuritis, paralysis and others. Hypovitaminosis B1 also leads to disruption of the pentose phosphate pathway of oxidation due to the lower activity of the enzyme transketolase.