PubMed Health⌕ Search

Biomedical subjects

L I Ostapchenko

Publications and source records attributed to L I Ostapchenko.

24 records · Page 2Linked to original sources
PubMedDate not supplied

[Post-radiation disturbances in the cyclic nucleotide system in rat spleen and thymus lymphocytes].

The changes in cAMP and cGMP content in rat spleen and thymus lymphocytes after irradiation in doses of 0.5 and 1 Gy, are determined, indicating to significant disturbances in the system of cyclic nucleotides. Radiation affected the functioning of enzymes both of synthesis and hydrolysis of cAMP and cGMP in spleen lymphocytes. The activity of adenylate cyclase and guanylate cyclase did not change in thymocytes after the exposure, while the activity of phosphodiesterase of cyclic nucleotides slightly increased.

Adenylyl Cyclases↗
PubMedDate not supplied

[Activation of cGMP-dependent protein kinase from spleen lymphocytes of rats exposed to radiation].

We have emanated and partially refined cGMP-dependent protein kinase from cytosolic fraction of lymphocytes. 12 hours after X-irradiation of animals in the doses of 0.5 and 1 Gr. Optimal conditions for the occurrence of phosphotransferase reaction have been also fixed. Concentration of enzymes protein was 0.4 mg/ml, Mg(2+)-10 mM, pH-7.5-8.0 and incubation time 20 min. The purified enzyme was maximally active at 10(-7) M cGMP. Protein kinase activity had a dose-dependent character: the doses being increased the effect becomes stronger.

Animals↗
PubMedDate not supplied

[Autophosphorylation in regulation of activity of cAMP-dependent protein kinases from spleen lymphocytes under ionizing radiation].

It was found that the irradiation in doses 0.5 and 1 Gy does not make any essential effect on the process of the autophosphorylation of cAMP-dependent protein kinases, extracted from the spleen lymphocytes 12 hours after exposure to the radiation. However, the decrease in the affinity of the holoenzyme to the cyclic nucleotide was found. The increase of the dose leads to the intensity of the effect (0.5 Gy--1.5 times decrease, 1 Gy--3 times decrease).

Animals↗
PubMedDate not supplied

[Effect of x-irradiation on the properties of cyclic AMP-dependent protein kinases from rat spleen lymphocytes].

It was shown, that in conditions of acute radiation affection in doze 0.5 and 1 Gy, there was a decrease of 32 and 55% in activity of cyclic AMP-dependent protein kinases, isolated from cytosol of lymphocytes. The analysis of cAMP-dependent protein kinases properties has shown, that disturbance in the interaction of the enzyme with protein substrate of phosphotransferase reaction and main modulater enzymes activity--cAMP proceeds of the ionising radiation effect.

Animals↗