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In rats with hyper- and hypovitaminosis the contents were determined of acid mucopolysaccharides (MPS) on the basis of contents of hexuronic acids; the total contents of biopolymers containing hexosamines (acid MPS, glycoproteins), on the basis of contents of hexosamines in the aortic wall and in the liver; and the activity of glutamine-fructose-6-phosphate aminotransferase (GPAT; EC 2.6.1.16) in the liver. Menadione-induced K hypervitaminosis was accompanied by moderate elevations of indicators of MPS metabolism. Protracted administration of ethyl biscoumacetate or sodium salicylate lowered the contents of acid MPS and of biopolymers containing hexosamines in the aortic wall and in the liver. Simultaneously, the GPAT activity in the liver markedly decreased.

It has been shown that pregnancy specific beta 1-globulin (SBG) is found in the rat blood serum on the 6--7th day of pregnancy. SBG reaches the maximum by the end of pregnancy and is not detected already at the 3d--4th day after delivery. The placenta is the site of the SBG snythesis. Other organs of the pregnant rat are not able to incorporate radioactive aminoacids into the protein in vitro.

The blood catecholamine, 11-hydroxycorticosteroid and free hydroxyproline content and collagen metabolism in the rabbit aortic wall were studied under conditions of chronic electrostimulation and bilateral amygdaloid electrocoagulation. It was found that electrostimulation of the amygdaloid lateral nucleus causes changes in the adrenocorticotropin content, activating collagen metabolism and accumulation in the aortic wall. A fall of the noradrenaline, 11-hydroxycorticosteroid concentration and activation of collagen metabolism, accompanied by its accumulation in the aortic wall, are seen during the 1st month after electrocoagulation.

The content of carbohydrate-containing bipolymers in the tissues of aorta, skin and blood serum of rabbits was studied under the effect of electrostimulation of supraoptical, ventromedial and medial mammillary nuclei of hypothalamus. The stimulation of supraoptical and ventromedial nuclei of hypothalamus is shown to be accompanied by an increase in the amount of collagen, glycosaminoglycans, sialic acids and glycoproteins which was estimated by the content of protein and hexosamines. Stimulation of the medial mammillary nucleus causes opposite changes.