The combined influence of the intermittent normobaric hypoxia and melatonin on morphofunctional activity of the rat's liver parenchyma

R. Yanko
O. O. Bogomoletz Institute of Physiology National Academy of Science of Ukraine, Kyiv


The aim of the study was to investigate the morphological changes in the liver parenchyma of rats after the combined effect of intermittent
normobaric hypoxia (INH) and melatonin.
The study was carried out in the spring on 24 male rats of the Wistar line. The experimental animals were daily given a hypoxic gas
mixture (12 % oxygen in nitrogen) in the intermittent mode: 15 minutes deoxygenation / 15 minutes reoxygenation for 2 hours. The same
rats were daily administered orally with exogenous melatonin at 10.00 at a dose of 5 mg / kg. The duration of the experiment was 28 days.
Histological preparations from the liver tissue were prepared according to a standard procedure. Morphometry was performed using the
computer program "Image J". In rats exposed to INH and melatonin, a significantly larger area of hepatocytes, their nucleus and cytoplasm
were detected by 19, 54 and 31 %, respectively, than in the control. This led to a significant increase in the nuclear-cytoplasmic ratio by
35 %. The experimental animals showed a higher number of nucleolus in the nucleus of hepatocytes (by 14 %) and the number of binuclear
hepatocytes (by 23 %). These data may indicate an increase in the functional activity of hepatocytes, the activation of physiological cell
regeneration at the intracellular level. Also, experimental animals showed a decrease in the distance between the nucleus of adjacent
hepatocytes, which indicates a more dense arrangement of cells among themselves and a decrease in the amount of intercellular
connective tissue. The combined effect of intermittent normobaric hypoxia and melatonin has morphological signs of increased functional
activity and physiological regeneration of the liver parenchyma.


liver, intermittent hypoxia, melatonin

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Received in editorial: 26.09.2018

Received the revised version: 29.10.2018

Signed for press: 29.10.2018


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