Прооксидантно-антиоксидантний баланс у серці щурів з різною поведінковою активністю за умов світлової експозиції

Abstract

The purpose of the article. The article shows that the effect of round-the-clock lighting causes changes in the processes of lipid peroxidation and antioxidant activity in rats, and depends on their behavioural activity. The effects of lighting on the processes of oxidative metabolism of varying degrees in the heart of resistant and unstable to emotional stress rats. Materials and methods. Investigations were carried out on 32 mature Wistar rats, divided into four groups: group 1 – animals resistant to emotional stress (intact); group 2 – intact animals unstable to emotional stress; group 3 – experimental animals resistant to emotional stress (30-day light exposure (1000 lux)); group 4 – experimental animals, unstable to emotional stress (30-day light exposure (1000 lux)). When assessing the effect of light on the state of the organism, the most important integral indicator is the behavior of animals. Therefore, during the experiment we used the observation of behavioral reactions in the test “open field”. Based on the characteristics of the behavior of animals in the “open field” rats were divided into groups resistant and unstable to emotional stress. To assess lipid peroxidation in the heart homogenate, the concentration of TBA-active products, the concentration of diene, oxidiene and triene conjugates were determined. Antioxidant processes were assessed by the increase in the concentration of TBA- active products during 1.5-hour incubation in an iron-ascorbate buffer solution, as well as by the activity of superoxide dismutase and catalase. Results and discussion. Prooxidant activity was characterized by an increase in the concentration of TBA-reactive substances in animals resistant to emotional stress. The concentration of TBA-reactive substances after 1.5-hour incubation increased in both experimental groups. Changes in the antioxidant status were illustrated by an increase in superoxide dismutase activity in the group of stress-unstable rats, whereas catalase activity increased in both experimental groups. In addition, in the group of animals resistant to emotional stress, a significant decrease in the resources of α-tocopherol and β-carotene was revealed. Conclusion. The long-term light exposure promotes the formation of end products of peroxidation in the heart of rats resistant to emotional stress and causes a decrease in antioxidant potential, regardless of behavioural activity. Antioxidant activity in the heart of emotionally stress-resistant rats is realized through both the enzyme and non-enzyme links of the antioxidant defence, while the main role in the heart of emotionally stress-resistant rats is played by superoxide dismutase activity