Features of the circadian rhythm in the size of mitochondria of rat hepatocytes under conditions of dark deprivation and chronic alcohol intoxication

Abstract

Background Circadian rhythms (CR) of functions and processes in the body are normally strictly coordinated with each other and with environmental factors, which ensures the maintenance of the functioning of the organs and systems of the body at an optimal level. However, we have not found any studies devoted to the study of CR of hepatocyte organelles under experimental conditions. Aim of study Study of the daily dynamics of the cross-sectional area of hepatocyte mitochondria in rats under conditions of dark deprivation, chronic alcohol intoxication and the combined effect of these factors. Materials and methods The work was performed on 80 males and 80 females Wistar rats, divided into 4 groups of each sex. Group 1 was kept under a fixed light regime; The 2nd group was kept under conditions of dark deprivation; the 3rd group was kept in the same conditions as the animals of the control group, but were subjected to chronic alcohol intoxication; Group 4 was kept in conditions of dark deprivation and subjected to chronic alcohol intoxication. Liver samples, after fixation and wiring, were analyzed using a transmission electron microscope. Micromorphometric methods were used to assess the mitochondrial apparatus of hepatocytes. Results In hepatocytes of rats from experimental groups of both sexes, CR of the cross-sectional area of mitochondria with similar parameters was detected. Dark deprivation and chronic alcohol intoxication, acting both separately and together, cause a restructuring of the mitochondrial size distribution, which is more pronounced in males. Conclusion The study indicates that the CR of mitochondrial size is dependent on the lighting regime and the toxic effect of ethanol and its metabolites. The size ranges of mitochondria in hepatocytes of females, compared to males, are more resistant to the effects of dark deprivation and alcohol intoxication.