The State of Oxidative Metabolism in the Cardiac and Skeletal Muscle Tissue in Conditions of Light Deprivation

The article considers the features of oxidative metabolism of cardiac and skeletal muscle tissue in the changed photoperiod, under the influence of round-the-clock light deprivation in combination with the introduction of exogenous melatonin. Material and methods. The experimental study was performed on male Wistar rats. Two groups were formed for research: intact and experimental. The animals of the intact group were in standard housing and feeding conditions, without changes in light regime. The animals of the experimental group for 30 days were in conditions of round-the-clock light deprivation on the background of the introduction of melatonin at a dose of 1.0 mg/kg body weight. Results and discussion. The level of production of reactive oxygen species was evaluated by the formation of a superoxide anion radical. To assess the prooxidant-antioxidant system in the homogenate of the studied tissues was determined by the concentration of thiobarbituric acid reactive substances. The efficiency of the enzyme link was evaluated by catalase and superoxide dismutase activity. We revealed an increase in the production of superoxide anion radical due to the activity of phagocytes compared to the intact group in the heart muscle under conditions of light deprivation on the background of the introduction of melatonin. In skeletal muscle tissue homogenate the production of superoxide anion radical by the mitochondrial electron transport chain production is likely was reduced compared to the intact group. Light deprivation on the background of exogenous administration of melatonin reduces the intensity of production of reactive oxygen species, which is confirmed by a decrease in the level of superoxide anion radical in the homogenate of the quadriceps femoris muscle tissues of experimental animals. Melatonin as an antioxidant reduces the production of superoxide anion radical by mitochondrial oxidation in the quadriceps femoris muscle. In this case, the excess melatonin stabilizes the fluidity of the membrane, reducing its permeability, which may indicate the protective properties of this substance. Conclusion. Thus, modeling the conditions of excess melatonin modifies the generation of superoxide anion radical from various sources. The above experimental conditions contribute to multidirectional changes in the quantitative generation of the superoxide anion radical in the heart and skeletal muscles. Changes in the indicators of prooxidant-antioxidant status in the homogenate of the studied tissues under the selected experimental conditions were not detected