Effect of dexamethasone on the expression of binding sites for high-density lipoproteins in cultured rat hepatocytes (Independence of the hormone effect on the intracellular cholesterol pool)

It is shown that glucocorticoids play a key regulatory role directed toward the maintenance of an optimal level of binding and internalization of HDL₃ in hepatocytes. Their stimulatory effect on the expression of HDL receptors proves to be independent of changes in the CH content in parenchymal cells. Translated fromByulleten' Eksperimentalnoi Biologii i Meditsiny, Vol. 117, N ^o 1, pp. 50–53, January, 1994     

Nuclear manifestation of prolactin receptors in rat hepatocytes and effect of prolactin

Ligation of the common bile duct induced intense nuclear expression of prolactin receptors in hepatocytes of male and female rats. Bromocriptin abolished this effect in female, but not in male rats. In males with ectopic pituitary transplants, nuclear and cytoplasmic manifestations of prolactin receptors in hepatocytes decreased. It is concluded that prolactin exerted a sex-dependent effect on the content of prolactin receptors in hepatocyte nuclei in rats. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 127, No. 5, pp. 579–582, May, 1999     

Correlation of prolactin concentration with levels of other hormones and with ultrastructural morphometric parameters of the testes in the human fetus

Consideration is given to the correlations between variations of the prolactin concentration and other hormonal parameters in the human embryonic period. The interrelation between the prolactin concentration and ultrastructural parameters of the testes is also traced. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 6, pp. 654–656, June, 1995 Presented by O. V. Volkova, Member of the Russian Academy of Medical Sciences     

Morphological and functional characteristics of human pituitary lactotrophic adenomas in cell cultures

Some features of the morphological cellular structure of prolactin secreting human pituitary adenomas and their secretion of prolactin and somatotropic hormone in primary suspension cultures were investigated. A possiblein vitro proliferation of lactotrophs was established. The inhibitory effect of somatostatin and its synthetic analog sandostatin, on prolactin secretion in prolactinomas was found to be less than in somatotropic hormone-secreting pituitary tumors. Presented by A. N. Konovalov, Member of the Russian Academy of Medical Sciences Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 11, pp. 543–546, November, 1994     

Peculiarities of the prolactin receptor expression in liver cells after partial hepatectomy

Changes in the expression of prolactin receptors in the liver in response to partial hepatectomy are studied in gonadectomized male and female rats using the indirect immunoperoxidase method. Experiments reveal the rise of prolactin receptor expression only at the early stages of regeneration (15 and 30 min postoperation). Intense expression of prolactin receptors in vesicular hepatocyte membranes coincides with lipid infiltration and high mitotic activity of hepatocytes 35 h after initiation of regeneration. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 9, pp. 351–355, September, 1997     

Morphofunctional aspects of liver regeneration in experimental correction of toxic hepatitis

It is demonstrated that cytoplasmic extract of rat pup liver stimulates cellular and intracellular regeneration of hepatocytes exposed to the toxic agent CCl₄. Injection of liver cytosol stabilizes lysosomal membranes, increases the coefficient of energy efficiency of mitochondria, and activates proliferation of polyploid hepatocytes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 6, pp. 656–659, June, 1995 Presented by D. S. Sarkisov, Member of the Russian Academy of Medical Sciences     

Effect of bromocriptine on the expression of prolactin receptors in liver cells after common bile duct ligation

Immunoperoxidase method combined with cytofluorimetry showed that in contrast to hepatocytes, enhanced expression of prolactin receptors on rat cholangiocytes induced by common bile duct ligation cannot be suppressed by the prolactin secretion inhibitor bromocriptine. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 7, pp. 52–55, July, 1998     

Glucocorticoid-dependent regulation of the expression of high-density lipoprotein binding sites in rat hepatocytes

It is shown that dexamethasone increases the number of HDL binding sites in cultured hepatocytes bothin vivo andin vitro. The glucocorticoid acts in a dose-dependent and reversible manner within a wide range of concentrations, including physiological and subphysiological doses. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 1, pp. 47–50, January, 1994     

Karyometric analysis of hepatocytes of common field mice from regions with different levels of technogenic contamination

Increased polyploidy of hepatocytes is shown using karyometric analysis in common field mice from different Altai regions with high levels of technogenic contamination of radiation and chemical nature. A higher degree of polyploidy is noted in animals with more marked alterations in hepatocytes classified as dystrophic and necrobiotic. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 2, pp. 223–227, February, 1996 Presented by D. S. Sarkisov, Member of the Russian Academy of Medical Sciences     

Comparative histophotometric characteristics of the structural-metabolic heterogeneity of hepatocytes in peritonitis and limb gangrene

Comparative histophotometric and correlation analysis was carried out to study dehydrogenase activity in hepatocytes of different acinar zones in peritonitis and gangrene of the lower extremities. Structural-metabolic disturbances of hepatocytes were found to be responsible for the weakened detoxicating function in patients with endotoxicoses. Special features of metabolic disturbances in the liver acini were demonstrated in peritonitis and limb gangrene. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 1, pp. 108–112, January, 1995 Presented by D. S. Sarkisov, Member of the Russian Academy of Medical Sciences     

Morphological characteristics of lymphocyte-hepatocyte contacts in various periods of liver regeneration in mice

The histo-and ultrastructure of regenerating murine liver is studied after excision of 2/3 of its tissue. Counts of leukocytes and lymphocytes are found to be increased in the intertrabecular spaces after the operation. Lymphocytes come in close contact with hepatocytes and reticuloendotheliocytes forming microtunnels at the sites of contact. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 2, pp. 176–179, February, 1994     

Effect of various oxygen concentrations on the ATP content in isolated hepatocytes of rats adapted and nonadapted to hypoxia

It is shown that isolated hepatocytes are capable of perceiving slight changes in the envioronmental oxygen concentration. A complicated phase dependence exists between adenosine triphosphate and partial oxygen pressure, which differs in cells from animals with high and low resistance to hypoxia, the former showing a more stable and resistant energy-synthesizing function than the latter. After long-term adaptation to periodic hypoxia, the resistance of the energy-synthesizing function rises in hepatocytes from high-resistant animals, and falls in low-resistant animals suggesting a fundamentally different organization of the emergency compensatory mechanisms of the energy-synthesizing function in hepatocytes of animals of these two types. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 12, pp. 576–581, December, 1994     

Role of the interaction between different types of serotonin and α2-adrenergic receptors in the regulation of audiogenic seizures in DBA/2 micereceptors in the regulation of audiogenic seizures in DBA/2 mice

It is shown that the serotonin receptors 5-HT_1c, 5-HT₃, and 5-HT₄ and α₂-adrenergic receptors are involved in the regulation of audiogenic seizures in DBA/2 mice, and that the effects of these serotonin receptors on the duration and magnitude of convulsive activity are the opoosite of those produced by α₂-adrenergic receptors. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 4, pp. 381–383, April, 1995     

Role of glycolysis in the maintenance of the energy-synthesizing function of hepatocytes from rats adapted and nonadapted to hypoxia at different oxygen concentrations

It is demonstrated that the lactate-Po₂ dependence is the same in hepatocytes of rats with high and low resistance to hypoxia and does not correlate with phasic changes in the ATP concentration in the 890–50 μM O₂ region. Strong activation of lactate formation against the background of ATP decrease indicates that glycolysis is not the major mechanism determining the steady-state ATP level in the cell and affecting the ATP-Po₂ relationship in a wide range of oxygen concentrations. The intensity of glycolysis in hepatocytes of rats with high resistance to hypoxia is markedly increased after periodic adaptation to hypoxia but remains practically unchanged in the hepatocytes of low-resistance rats. This indicates that fundamentally different compensatory mechanisms are involved in this process in the liver of high- and low-resistance rats. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 1, pp. 28–32, January, 1995     

Ultrastructure of hepatocytes and sinusoidal endothelial cells for the use of competition between lysosomotropic preparations applied in the treatment of iron-deficiency anemia

It is shown that the level of repair processes in endothelial cells progressively declines in posthemorrhage iron-deficiency anemia treated with Ferrum Lek. Administration of Ferrum Lek inhibits the repair processes in hepatocytes, leading to the development of dystrophy and necroses in them. Administration of rheopolyglucin prior to Ferrum Lek reduces the Ferrum Lek content in endothelial cells lysosomes and activates the repair processes in hepatocytes and endothelial cells. This is thought to be due to competition of rheopolyglucin for cell vacuoles and the ability of this preparation to stimulate the repair processes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 11, pp. 517–520, November, 1994 Presented by Yu. I. Borodin, Member of the Russian Academy of Medical Sciences     

Intracellular ceruloplasmin-like protein of mammals

Pulse-chase experiments show that, in addition to the secreted molecular forms of ceruloplasmin, an intracellular ceruloplasmin-like protein is synthesized in rat hepatocytes. Radioimmunochemical assay demonstrates that a nonserum isoform of ceruloplasmin is bound to the Golgi membranes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 1, pp. 83–85, January, 1994 Presented by A. N. Klimov, Member of the Russian Academy of Medical Sciences     

The invertor mechanism of changes in the plasma membranes of hepatocytes during induction of microsomal monooxygenases in adult and old rats

Age-specific changes of some parameters of the state of the plasma membrane are studied for genetic induction of enzymes of microsomal oxidation. Changes of the state of plasma membrane of hepatocytes are shown to be associated with the synthesis of a specific intracellular regulator (invertor). Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 1, pp. 13–15, January, 1994     

Effect of paraoxon and sulfhydryl reagents on3H-quinuclidinol benzoate and3H-methylscopolamine with synaptic membranes of rat brain

Paraoxon is shown to reduce the density of M-choline receptors in the cortex of rat brain. Inhibition of³H-QNB is noncompetitive and reversible in nature. Sulfhydryl reagents do not affect this process. The mechanism of action of PO is thought to include direct effects on brain muscarine receptors. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 7, pp. 51–53, July, 1994     

Comparative analysis of progesterone and estradiol reception in human myoma

Cytosolic and plasma membrane receptors for progesterone and estradiol are studied in myomatous nodes (MN) and in histologically unaltered myometrium (HUM) against the background of myoma. The level of cytosolic receptors for both hormones is higher in the myoma cells than in the essentially healthy myometrium. In the plasma membranes the progresterone reception is reduced and the estradiol reception is unchanged compared with HUM. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 7, pp. 33–34, July, 1994     

Effect of experimental hyperprolactinemia on the sexual cycle and folliculogenesis

It is found that hyperprolactinemia results in the development of stable anovulation, in which the disruption of folliculogenesis sets in as early as at the stage of late preantral (graafian) follicles and manifests itself in a decrease of the mitotic activity in cells of the membrana granulosa. The concentration of follicle-stimulating hormone thereupon changes to different extents or remains at the control level. A direct influence of prolactin on intrafollicular estrogen production and on cell division is postulated. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 9, pp. 326–328, September, 1994