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V T Ivashkin

Publications and source records attributed to V T Ivashkin.

At least 127 records · Page 7Linked to original sources
PubMed1985

[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. It is supposed that changes in the activity of casein kinase in the stomach mucosa at the late carcinogenesis stages are associated with the neoplastic transformation and precede the appearance of morphological characters of the malignization.

Animals↗
PubMed1984

[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. The data obtained are suggestive of the possibility of using the above-indicated findings for the biochemical diagnosis of malignant neoplasms.

Casein Kinases↗
PubMed1982

[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. The blockade could be prevented with dibutyryl-cAMP. The seasonal dependence of activation of HCl secretion by specific and unspecific modifiers was discovered. The data obtained show the necessity of preliminary activation of adenylate cyclase and accumulation of limiting content of cAMP for the utilization of succinate in reactions of generation and transport of H+ by acid-producing cells of isolated gastric mucosa in frog.

Adenylyl Cyclases↗
PubMed1982

[Trigger function of cyclic AMP in the initiation of HCl secretion by the frog gastric mucosa].

Histamine (0.3 mM) caused a rapid but transient increase in cAMP level prior to a rise in HCl secretion in the isolated gastric mucosa of frog Rana esculenta. H2-receptor blocking agent cimetidine (0.01 mM) suppressed HCl secretion which had been preceded by a decrease in cAMP level. No statistically significant changes in cGMP content were found. Dibutyryl cAMP imitated the effect of histamine. In frogs captured in spring, with a high level of HCl secretion and high content of cAMP, histamine exerted no stimulating effect. It seems to be the cAMP and not cGMP that acts either as a trigger in activation of HCl secretion or as a stabilizer of induced secretion.

Animals↗
PubMed1976

[Relation between oxidation and phosphorylation in gastric mucosa mitochondria].

The authors studied the state of cell respiration and oxidative phosphorylation in the mitochondria of the gastric mucosa at various phases of its function. Stimulation of secretion with histamine led to a distinct increase in the rate of mitochondrial respiration in the gastric mucosa against the background of a marked fall of the conjugation coefficient level, including P/O. The mentioned changes in the energy conjugation of mitochondria of the parietal cells preceeded activation of HCl secretion.

Animals↗