CIRCADIAN RHYTHM OF HISTOCHEMICAL, AUTORADIOGRAPHIC AND CYTOMETRIC INDICES IN MICE HEPATOCYTES AT THE VARIOUS STAGES OF ONTOGENESIS

Objective - to study the diurnal organization of the most important parameters of liver cell structure and metabolism in mice during postnatal ontogenesis. Materials and methods. Diurnal changes in the metabolic indices of the liver of mice were studied using cytochemistry and image cytometry. RNA and glycogen were demonstrated by cytochemical methods. The image cytometry was applied for assessing the area of section occupied by liver cells, the volume of the nuclei and nucleoli, nuclear-cytoplasmic ratio, the incorporation of 3H-uridine in hepatocytes, and glycogen content in the liver of mature, presenile and senile mice. Results. Diurnal organization of the liver metabolic parameters was strongly pronounced in mature (adult) age. During this period, the largest amplitudes of the daily dynamics - deviations from the average daily levels - were detected. Mice at the later ontogeny stages (presenile and senile age), compared to adult mice, showed changes in mesor (average daily level), acrophases shifts and reduced amplitudes of measured parameters. Conclusions. The reduction in amplitudes of hepatocyte metabolic parameters indicates the attenuation of the liver functional capacities in the old age and demonstrates age-dependent desynchronosis at the cellular level.

liver, hepatocytes, image cytometry, ontogeny, circadian rhythms