The activity of Krebs cycle enzymes in the visual analyzer of rats in the norm and under stress.

Higher activity of the NAD-dependent dehydrogenases of the tricarboxylic acid cycle (TAC) is observed in the optic retina, and of FAD-dependent dehydrogenases in the occipital lobes of the brain, in the visual analyzer of intact rats. The influence of stress using Desiderato's method induces a compensatory increase in the activity of succinate dehydrogenase. Acute stress induces a change in the regulation of the activity of the TAC dehydrogenases, assessed on the basis of the reaction to functional load. The animals' remaining in the dark following stress promotes the restoration of the activity of the TAC cycle to the normal level.

[The activity of Krebs cycle enzymes in the visual analyzer of normal rats and under stress]. / Aktivnost' fermentov tsikla Krebsa v zritel'nom analizatore krys v norme i pri stresse.

In the visual analyzer of the intact animals higher activity of NAD-dependent dehydrogenases of tricarbonic acids cycle is observed in the retina and of FAD-dependent dehydrogenases in the occipital brain lobes. The influence of stress by Desiderato method elicits compensatory increase of the succinatedegidrogenase activity. The acute stress elicits a change of regulation of the activity of dehydrogenase of tricarbonic acids cycle, estimated by the reaction to functional load. Animals staying in the darkness after stress promotes restoration of the tricarbonic acids cycle of the enzymes activity up to the normal level.

[Succinate dehydrogenase activity of the retina and occipital lobe of the brain during emotional stress]. / Aktivnost' suktsinatdegidrogenazy v setchatoi obolochke glaza i zatylochnykh doliakh bol'shikh polusharii golovnogo mozga pri émotsional'nom stresse.

The emotional stress induces changes in redox processes in the visual analyzer at the level of the succinic acid transformation in the Krebs cycle. The stress evokes a particularly sharp decrease in the succinate dehydrogenase activity in the retina under conditions of dark adaptation whereas in the occipital lobes under the same condition a considerable intensification of the succinic acid oxidation is observed. Stress action under ordinary conditions of the day and night change is accompanied by the succinate dehydrogenase activation in the visual analyzer. However, the light load increases the enzyme activity in test animals the same way as in intact animals.