[Protein kinase activity and phosphorylation of endogenous proteins in the rat colonic mucosa during chemical carcinogenesis].

Treatment with a single dose of 21 mg/kg, of 1,2-dimethylhydrazine was followed by a significant decrease in the level of cAMP-dependent protein kinase (histone kinase) in rats' large bowel mucosa after 72 hrs. However, its level returned to basal value after 2 weeks, with casein kinase level remaining unchanged. Both carcinogen--induced tumors of the large bowel and adjacent mucosa showed a drop in protein (mol.

[Change in the protein kinase activity of glandular stomach mucosa in rats during malignant transformation].

Changes in the activity of protein kinases in the glandular stomach mucosa of rat were studied in the case of carcinogenesis induced by N-methyl-N'-nitro-N'-nitrosoguanidine. No essential changes in the activity of cAMP-dependent protein kinase (histone kinase) were found in the mucosa as well as in tissues of the developed tumours of the rat glandular stomach. The activity of cAMP-independent protein kinase (casein kinase) increased significantly 3 months after the beginning of the carcinogen administration and at the late stages (after 12-15 months) it was decreased considerably both in the glandular stomach tumours and in the stomach mucosa without the characters of the malignant growth.

[Indices of protein kinase activity and the problem of biochemical diagnosis of malignant growth].

Protein kinase, cAMP-dependent and casein kinase activities and the ratio of these activities were determined in normal and neoplastic tissues of the colonic mucosa. Substantial activation of casein kinase and an appropriate decrease in the activity ratio of the enzymes were revealed in the malignant tissue. Protein kinase activity changed in a similar fashion in the histologically intact mucosa located 25-30 cm from the center of the tumor.

[Effect of the kallikrein-kinin system on gastric mucosa].

I. m.administration of andecalin increased vascular permeability, induced microhemorrhages in the gastric mucosa and intensified secretion of mucopolysaccharides in patients.

[Role of the adenylate cyclase system in utilization of succinate by the frog gastric mucosa].

Interrelationship between the adenylate cyclase system state and utilization of succinate as a substrate of oxidation in mechanisms of HCl secretion by isolated gastric mucosa of frog Rana esculenta was studied. The inhibition of the protein synthesis by cycloheximide rendered gastric mucosa insensitive to the activation of HCl secretion by histamine and succinate. A similar effect was exerted by cimetidine, a blocking agent for H2-receptors.

[Significance of studies on cyclic nucleotide metabolism for practical medicine].

Based on the results of own studies and data available in literature the evidence is given on peculiarities of determination and estimation criteria for the content of cyclic nucleotides in people. Changes in the metabolism of these substances and their pathogenic role are considered for a large number of diseases. Pharmacotherapeutic aspects are described, in particular regulation of enzymes taking part in the metabolism of cyclic nucleotides.