[Features of cholecalciferol hydroxylation in the liver of rats in conditions of D-hypervitaminosis and activity of alpha-tocopherol].

It is shown, that hepatocytes contain two (microsomal and mitochondrial) vitamin D3 25-hydroxylase enzymes, which differ as to their activity and function with maximal activity at different concentrations to substrate, namely at 15 microM and 100 microM of vitamin D3, accordingly. Activity of vitamin D3 25-hydroxylase enzymes of hepatocytes is regulated by cholecalciferol and alpha-tocopherol. The general and microsomal vitamin D3 25-hydroxylase enzymes activity of hepatocytes is lowered, but mitochondrial isoform is increased under D-hypervitaminosis conditions.

[Influence of vitamin E application period on the mineral and D-vitamin metabolism in the organism].

It was shown, that influence of vitamin E on mineral and D-vitamin metabolism depends on its doses and application period: physiological doses of vitamin E activate and large doses - inhibit the effect of vitamin D3 in regulation of mineral metabolism in the organism. The duration of application of large doses of vitamin E (higher than 20 physiological doses) during which the negative changes are not determined has not to exceed 10 days.

[Content and transportation of Ca(2+) to hepatocytes and lipid content of liver cell membrane structure in experimental diabetes in the rat].

It is proved that at experimental diabetes the calcium content in hepatocytes is disturbed. This disorder is mostly shown in increase of calcium content in hepatocytes and in decrease of accumulation of these ions in mitochondrias. One of the possible reasons of changes at this pathology is the change of lipid content of hepatocytes, mitochondrias and microsomes.