[Effect of novel derivatives of 1,2,4-triazolyl-5-mercaptoacetic acid on the reductase activity in the liver microsomes in adult and old rats with immobilization-induced stress]. / Izuchenie osobennostei vliianiia novykh proizvodnykh 1,2,4-trazolil-5-merkaptouksusnoi kisloty na aktivnost' reduktaz mikrosom pecheni vzroslykh i starykh krys pri immobilizatsionnom stresse.

The effect of 3-(4-pyridyl)-1,2,4-triazolyl-5-mercaptoacetic acid morpholinium salt (rumosol) and potassium salt (drug 2) on the liver microsomal reductase activity was studied in adult (aged 10-12 months) and old (22-25 months) Wistar rats under immobilization stress conditions. In the group of adult rats, both drugs showed comparable moderate inhibiting effect. In the group of old rats, rumosol injections produced the reductase activation up to a level characteristic of the intact old animals.

[Reductase activity in the liver microsomes in adult and old rats during immobilization stress]. / Aktivnost' reduktaz mikrosom pecheni vzroslykh i starykh krys pri immobilizatsionnom stresse.

The activity of NADH: and NAD(P)H:2,6-dichlorphenolindophenol reductases was investigated in liver microsomes of adult and old rats during immobilizing stress. There significant decrease of both reductases was found in old animals. Pronounced decrease of NADH:2,6-dichlorphenolindophenol reductase activity was found in adult immobilized rats.

[Activities of the liver microsome reductases in adult and aged rats during stress]. / Izuchenie osobennostei reguliatsii aktivnosti reduktaz mikrosom pecheni vzroslykh i starykh krys pri stresse.

The influence of 0.01% sodium dodecyl sulphate, 1.5 and 6.0 M urea and 0.03 M hydrogen peroxide to the NAD(P)H: 2,6 dichlorphenolindophenol reductase activity in livers of adult and old Wistar rats during immobilizing stress was interested. Obtained results indicate that the NADPH--dependent reductase is more resistant to modulating effect of sodium dodecyl sulphate, hydrogen peroxide and urea than NADH-dependent enzyme. The significant decrease of NADH: 2.6 dichlorphenolindophenol reductase sensitivity to the action of all studied modulators occurs in old rats. The similar changes appears in the adult rats liver during stress. The old rats immobilization is accompanied by a decrease of this enzyme activity and the reduction of the influence of all studied modulators to NADH: 2.6 dichlorphenolindophenol reductase as compared with adult ones. These changes in the activity and properties of microsomal NADH: 2,6 dichlorphenolindophenol reductase promote more pronounced decrease of the substrate hydroxylation in the liver of old rats during stress compared to adult ones.

[The content of pyridine coenzymes in the liver of the adult and old rats in stress]. / Soderzhanie piridinovykh kofermentov v pecheni vzroslykh i starykh krys pri stresse.

The concentration of oxidized and reduced NAD and NADP in the liver was studied in 36 adult (10-12 month old) and old (22-25 month old) male Wistar rats exposed to immobilization stress. It was established that content of piridine coenzymes in rat liver does not change with age. Immobilization stress decreases NADP reduction in adult animals, increases percentage of NADN in the total pool of reduced piridine coenzymes in the liver. In old stressed rats reduction of the NADP pool diminished accompanied by a distinct lowering of concentration of reduced NAD compared to its level in adult animals. It is suggested that shifts in the system of piridine coenzymes in the liver of adult rats support maintenance of effective function of the microsomal oxigenase chain in stress, in old animals promotes stress attenuation.