Dosed normobaric hypoxia as a non-medication approach of stimulation of physiological regeneration of liver parenchyma

There are only few studies in which the effect of intermittent normobaric hypoxia on the liver status in animals and people with arterial hypertension has been investigated. That’s why it’s necessary to carry out these studies in animals with high blood pressure. The purpose of this work was to carry out comparative studies of the effect of dosed intermittent normobaric hypoxia on the morphofunctional state of hepatocytes of normotensive (line Wistar) and spontaneously hypertensive (line SHR) rats, age 4 months. The experimental rats were daily exposed to hypoxic gas mixture (12% oxygen in nitrogen) in intermittent mode: 15 minutes deoxygenation / 15 minutes reoxygenation for 2 hours. The duration of the experiment was 28 days. Histological, morphometric and biochemical research methods were used. The histological preparations were made by the standard methods. The slides were photographed using a digital camera on the microscope "Nikon" (Japan). The morphometric analysis was performed on digital images using the computer program "Image J". The activity of cytochrome oxidase and succinate dehydrogenase enzymes in a suspension of hepatocytes mitochondria was determined by the method of R. S. Krivchenkov. An increase was observed in the size of hepatocytes and their nucleus, in the number of binuclear hepatocytes and nucleolus in the liver of both experimental lines of animals after exposure to intermittent normobaric hypoxia. The distance between adjacent nuclei of hepatocytes decreased. Cytochrome oxidase activity in a suspension of mitochondria increased. These morphological changes took place in the liver parenchyma of the both experimental lines of rats. But they were more pronounced in the liver of rats of the Wistar line than in the SHR line. Our data indicated that dosed normobaric hypoxia had a one-way, stimulating effect on the morphofunctional activity of hepatocytes, but the severity of this effect in rats of different lines was not the same. The obtained data can have not only theoretical value, but also be of some practical interest when using intermittent normobaric hypoxia for medical and health purposes in patients with impaired liver function and arterial hypertension.

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Morphological changes in the rat’s liver of different age after administration of magnesium chloride

Journal of the Belarusian State University Biology ◽

10.33581/2521-1722-2019-3-40-48 ◽

2019 ◽

pp. 40-48

Author(s):

Roman V. Yanko ◽

Elena G. Chaka ◽

Irina G. Litovka ◽

Mikhail I. Levashov

Keyword(s):

Magnesium Chloride ◽

Morphological Changes ◽

Serum Magnesium ◽

Liver Parenchyma ◽

Magnesium Content ◽

Male Rats ◽

Standard Diet ◽

Erythrocyte Suspension ◽

Physiological Regeneration ◽

Different Ages

The aim of the work was to study the morphological changes in the rat’s liver of different ages after prolonged administration of magnesium chloride. The experiments were performed on 48 Wistar male rats at 3 and 15 months of age. Experi mental animals, in addition to the standard diet, received magnesium chloride daily for 21 days at a dose of 50 mg / kg of body weight. Histological preparations were made from the liver tissue according to the standard method. The liver morphometry was performed on digital images using the computer program Image J. The content of magnesium cations was determined in the serum and suspension of red blood cells. Based on the results of our studies, it can be assumed that the administration of magnesium chloride activates the processes of physiological regeneration and functional activity of the liver parenchyma in rats of different ages. This is evidenced by an increase in the number of binuclear cells and nucleolus in the nucleus of hepatocytes, an increase in the nuclear-cytoplasmic and nucleolar-nuclear ratio. The relative area of the sinusoid network, the number and density of connective tissue cells were increased in the liver of 3-month-old experimental rats. This may indicate an increase of trophic and protective activity of the stroma in this organ. Experimental rats (15-month-old animals) revealed a moderate increasing in the erythrocyte suspension and blood serum magnesium content. The administration of magnesium chloride has the morphological features indicating an increasing of the physiological regeneration and activity of the liver parenchyma in young (to a greater extent) and adult animals.

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Effects of 5-5'-Diphenyl-2-thiohydantoin (DPTH) and Thyroxine on the Ultrastructure and Chemical Composition of Rat Liver

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100066917 ◽

1971 ◽

Vol 29 ◽

pp. 570-571

Author(s):

E. A. Elfont ◽

R. B. Tobin ◽

D. G. Colton ◽

M. A. Mehlman

Keyword(s):

Chemical Composition ◽

Rat Liver ◽

Future Study ◽

Mode Of Action ◽

Liver Mitochondria ◽

Rat Liver Mitochondria ◽

Effective Inhibitor ◽

Biochemical Effects ◽

Glycerophosphate Dehydrogenase ◽

Stimulation Of

Summary5,-5'-diphenyl-2-thiohydantoin (DPTH) is an effective inhibitor of thyroxine (T4) stimulation of α-glycerophosphate dehydrogenase in rat liver mitochondria. Because this finding indicated a possible tool for future study of the mode of action of thyroxine, the ultrastructural and biochemical effects of DPTH and/or thyroxine on rat liver mere investigated.Rats were fed either standard or DPTH (0.06%) diet for 30 days before T4 (250 ug/kg/day) was injected. Injection of T4 occurred daily for 10 days prior to sacrifice. After removal of the liver and kidneys, part of the tissue was frozen at -50°C for later biocheailcal analyses, while the rest was prefixed in buffered 3.5X glutaraldehyde (390 mOs) and post-fixed in buffered 1Z OsO4 (376 mOs). Tissues were embedded in Araldlte 502 and the sections examined in a Zeiss EM 9S.Hepatocytes from hyperthyroid rats (Fig. 2) demonstrated enlarged and more numerous mitochondria than those of controls (Fig. 1). Glycogen was almost totally absent from the cytoplasm of the T4-treated rats.

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Gap junctions in the prothoracic glands of the tobacco hornworm, Manduca sexta

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100123933 ◽

1992 ◽

Vol 50 (1) ◽

pp. 706-707

Author(s):

Ji-da Dai ◽

M. Joseph Costello ◽

Lawrence I. Gilbert

Keyword(s):

Gap Junctions ◽

Small Molecules ◽

Manduca Sexta ◽

Freeze Fracture ◽

Cell Communication ◽

Cellular Level ◽

Thin Sections ◽

Prothoracic Glands ◽

Polyhydroxylated Steroids ◽

Stimulation Of

Insect molting and metamorphosis are elicited by a class of polyhydroxylated steroids, ecdysteroids, that originate in the prothoracic glands (PGs). Prothoracicotropic hormone stimulation of steroidogenesis by the PGs at the cellular level involves both calcium and cAMP. Cell-to-cell communication mediated by gap junctions may play a key role in regulating signal transduction by controlling the transmission of small molecules and ions between adjacent cells. This is the first report of gap junctions in the PGs, the evidence obtained by means of SEM, thin sections and freeze-fracture replicas.

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