Effect of prenatal hypoxia on DNA synthesis in the tracheal epithelium and LPO-AOD system in the lungs of newborn rats

Newborn rats euthanized 24 h after birth were examined. The rats were born to females exposed to chronic hypobaric hypoxia on days 14–19 of gestation. The index of nuclei labeled with³H-thymidine in the tracheal epithelium of newborn rats exposed to prenatal hypoxia was 3 times lower than in the control. The LPO level was higher in posthypoxic animals than in intact rats. Prenatal hypoxia led to the suppression of antioxidant defense in the lungs of newborn rats. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 5, pp. 531–533, May, 1994     

Effect of the hydra peptide morphogen on posthypoxic disorders in rats exposed to prenatal hypoxia

Lipid peroxidation in the lungs and blood are activated while DNA synthesis in the tracheal epithelium and hepatocytes is inhibited during the first five days of postnatal life in rat pups after severe prenatal hypoxia. Intraperitoneal injection of the undecapeptide pGlu-Pro-Pro-Glu-Glu-Ser-Lys-Val-Ile-Leu-Phe, a peptide morphogen isolated from the hydra, before hypoxia normalizes lipid peroxidation in the lungs and blood of the five-day-old pups. A compensatory activation of DNA synthesis occurs in tracheal epithelium and hepatocytes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 123, No. 3, pp. 269–272, March, 1997.     

Effect of the hydra peptide morphogen on cell proliferation in the thymus of newborn rats exposed to prenatal hypoxia

Female rats were exposed to high-altitude hypoxia on days 14–19 of pregnancy. Thirty min before hypoxia the animals were injected with the hydra peptide morphogen in a dose of 10 μg/kg intraperitoneally. Prenatal exposure to hypoxia suppressed proliferative processes in thymic cortex and medulla in newborn rats and decreased the lymphocyte count in the female—newborn rat pairs and the percent of full-term deliveries. Injection of hydra peptide morphogen prevented the development of posthypoxic disorders in newborn rats. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 9, pp. 348–350, September, 1997     

Effects of regulatory peptides on DNA synthesis in duodenal smooth muscle tissues of albino rats during the early postnatal period

Effects of angiotensin II, endothelin-1, dermorphin A10 analogue, dalargin, and hydra peptide morphogen on DNA synthesis in duodenal smooth muscle cells of newborn albino rats were studied by³H-thymidine autoradiography. Angiotensin II and endothelin-1 increased the number of DNA-synthesizing myocytes and did not affect the labeling intensity. Dermorphin A10 analogue, dalargin, and hydra peptide morphogen had no effect on these indexes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 127, No. 6, pp. 651–653, June, 1999     

Effect of the hydra peptide morphogene at the early stages of rat postnatal ontogenesis

The effect of the hydra peptide morphogene, its structural fragment, and antagonist 5N pentapeptide on DNA production in the myocardium, tongue, gastric and tracheal epithelium was studied in 7-day-old rats. The hydra peptide morphogene stimulated proliferative activity of the myocardium and epithelium of different organs. 5N fragment did not affect the production of DNA in the myocardium and suppressed it in the epithelium. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 12, pp. 681–683, December, 1998     

Hydra peptide morphogen weakens poststress disturbances in albino rats

The effect of hydra peptide morphogen on poststress disturbances in albino rats is evaluated. A 4-h immobilization leads to a rise of corticosterone, activates lipid peroxidation, impairs antioxidant defense system, and induces a marked decrease in the content of thyrotropic hormone and thyroxine. The relative weight of the thymus significantly decreases 24 h after immobilization. Moreover, stress inhibits proliferative processes in corneal and pyloric epithelium immediately and 24 h after immobilization. Hydra peptide morphogen prevents the endocrine shift, normalizes the content of lipoperoxides and α-tocopherol immediately after stress, weakens poststress proliferation disturbances, induces compensatory stimulation of proliferative processes in the corneal epithelium 24 h after stress, and normalizes DNA synthesis in the pyloric epithelium, the level of malonic dialdehyde being elevated. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 10, pp. 392–395, October, 1997     

Effects of hydra peptide morphogen and its analogue and fragments on DNA synthesis in tracheal epithelium and smooth muscle cells in newborn albino rats

Hydra peptide morphogen, its Arg⁷ analogue, and 6C, 3C, and 5N fragments were injected intraperitoneally in a dose 10⁻⁷ mol/kg to newborn rats from the 2nd to 6th day of life. Autoradiography with³H-thymidine showed that hydra peptide morphogen and its 6C fragment stimulated DNA synthesis in tracheal epitheliocytes, but inhibited this process in smooth muscle cells. 5N fragment inhibited DNA synthesis in both tissues, while 3C and Arg⁷ were ineffective. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 129, No. 6, pp. 646–649, June, 2000     

Mechanisms responsible for the resistance of tracheal smooth muscle to histamine in rats

A mechanographic study of contractile responses by tracheal smooth muscle segments of rats to a histaminergic agent showed that intact segments did not respond to histamine in the concentrations used (0.01–10 μM), whereas depolarized segments responded to histamine by dose-dependent contraction which were considerably enhanced following mechanical removal of the tracheal epithelium. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 9, pp. 263–264, September, 1995     

Content of 2,3-diphosphoglycerate and adenosine triphosphate in erythrocytes and the acid-base balance in adult and newborn rats during acute hypoxia

It is shown that in deep acute hypoxic hypoxia the 2,3-diphosphoglycerate content is reduced and the adenosine triphosphate content unchanged in the erythrocytes of newborn rats. Under the same conditions adult animals show an increase of 2,3-diphosphoglycerate and a drop in the adenosine triphosphate content in the erythrocytes. The importance of these changes is discussed in terms of the mechanisms regulating the oxygen-transporting function of erythrocytes during acute hypoxic hypoxia in newborn and adult animals. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 6, pp. 631–633, June, 1995 Presented by M. Ya. Studenikin, Member of the Russian Academy of Medical Sciences     

Effect of endothelin-1 on DNA synthesis in tracheal epithelium and smooth muscle cells in newborn albino rats

Repeated (5-fold) intraperitoneal injections of 5×10⁻⁹ mol/kg endothelin-1 inhibited DNA synthesis in tracheal epitheliocytes and activated lipid peroxidation in the lungs of newborn rats. Endothelin-1 in a dose of 5×10⁻⁸ mol/kg stimulated proliferative activity of tracheal smooth muscle cells and intensified lipid peroxidation in the blood, which aggravated observed changes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 129, No. 3, pp. 294–296, March. 2000     

Effect of synthetic analogs of dermorphin on mitosis in the corneal and lingual epithelium of albino rats

A study of the effects of synthetic analogs of dermorphin which are prime agonists of the μ-opiate receptors, on cell division in the corneal and lingual epithelium of albino rats showed that both analogs depressed DNA synthesis in the corneal and lingual epithelium 4 h after administration. In the lingual epithelium DNA synthesis and the mitogenic index were still depressed 24 h after drug administration. In the cornea cell division parameters had normalized by this time. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 11, pp. 508–510, November, 1994 Presented by Yu. A. Romanov, Member of the Russian Academy of Medical Sciences     

Effect of opioid lymphostimulation on the microcirculation in pial vessels of the ischemized rat brain

The response of pial vessels to i.p. administration of leu-enkephalin (at 40 μg/kg) is studied biomicroscopically in the control, before and after bilateral occlusion of the common carotid arteries. Leu-enkephalin causes chiefly the narrowing of pial arterioles and does not affect venule diameter. The effect of leu-enkephalin on occlusion of the common carotid arteries manifests itself in the preservation of circulation stability, the narrowing of some arterioles, and in the decrease of the degree of dilation. These changes occur against the background of lowered arterial pressure, bradycardia, increased local circulation in the brain cortex by 50–70%, intensification of the lymph flow in micro- and macrovessels, and the absence of mortality of animals in the first hours of occlusion of the arteries. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 1, pp. 100–105, January, 1995 Presented by G. N. Kryzhanovskii, Member of the Russian Academy of Medical Sciences     

Effect of substance P on the content of catecholamines and on the enzymes of their synthesis in the brain of chronically alcoholized rats

The effect of a single administration of the endogenous peptide substance P on the content of dopamine (DA), and norepinephrine (NE), and on the activity of tyrosine hydroxylase (TH) and dopamine β-hydroxylase (D-β-H) is studied in the hypothalamus and midbrain of rats after a 6-month alcoholization. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 7, pp. 46–48, July, 1994     

Correction of hyperlipoproteinogenic microangiopathy and organ pathology with thymalin and leu-enkephalin in the early stages of atherogenesis

The effects of thymalin and leu-enkephalin on lipid peroxidation and microcirculatory disorders in the early stages of atherogenesis are compared. Correction of the generalized microcirculatory response to hyperlipoproteinemia with the peptides manifested itself in the regression of atherosclerotic lesions in the aorta and restoration of the morphofunctional state of the myocardium and liver. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 1, pp. 108–111, January, 1996     

Effects of Analogues of Hydra Peptide Morphogen on DNA Synthesis in the Myocardium of Newborn Albino Rats

DNA-synthetic activity of myocardial cells was studied by 3H-thymidine autoradiography in newborn albino rats after intraperitoneal injection of hydra peptide morphogen and its analogues. Administration of hydra peptide morphogen stimulated proliferative activity in the myocardium. Short analogues of hydra peptide morphogen, 6C and 3C peptides, produced a similar effect. Administration of arginine-containing analogue of hydra peptide morphogen significantly reduced the number of DNA-synthesizing nuclei in the ventricular myocardium of newborn albino rats. The role of the structure of the peptide molecule in the realization of the morphogenetic effects of hydra peptide morphogen is discussed.     

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     

Lipid peroxidation parameters in the internal organs of rats with different degrees of resistance to hypoxia

Lipid peroxidation and the antioxidant system of the heart, liver, and brain are studied in adult male Wistar rats with high and low resistance to hypoxia tested by “raising” to an altitude of 11.5 km and in intact outbred rats. These parameters are found to be the same in the brain of low- and high-resistance rats, while the brain content of lipid peroxidation products is higher in both groups of Wistar rats compared with outbred rats. The heart and liver parameters are coupled to the resistance to hypoxia. Antioxidant activity prevails over lipid peroxidation in the hearts and livers of high-resistance rats, confirming that oxidation plays a major role in the damaging and lethal effects of acute hypoxia. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 1, pp 26–29, January, 1996 Presented by A. I. Archakov, Member of the Russian Academy of Medical Sciences     

Impaired plasticity of hippocampal synaptic transmission in rats exposed to prenatal hypoxia is normalized by treatment with nootropic dipeptides

Experiments on hippocampal slices from young rats exposed to hypobaric hypoxia duringin utero development revealed enhanced responsiveness (an increase in a CA1 field response amplitude) and reduced plasticity (a low incidence of field response long-term potentation following high-frequency stimulation) of CA1 pyramidal neurons. Postnatal treatment of animals with piracetam peptide analogs constructed on the basis of pyroglutamate and proline normalized both these physiological indices. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 12, pp. 592–595, December, 1995 Presented by G. N. Kryzhanovskii, Member of the Russian Academy of Medical Sciences     

Effects of adaptation to periodic hypoxia on kinetic parameters of respiratory chain enzymes in rat brain

A study of kinetic parameters of brain respiratory enzymes revealed that the maximal velocity and the Michaelis apparent constant for NADH-cytochrome C-reductase are significantly lower in low-resistant rats than in rats with a high resistance to hypoxia. Adaptation to periodic hypoxia increases total resistance only in low-resistant rats. It is accompanied by an increase in the values of kinetics parameters for NADH-cytochrome C-reductase and cytochrome oxidase. Kinetic parameters for these enzymes in the brain of high-resistant rats are either unaltered or even decreased. It is suggested that the first enzymatic complex of the respiratory chain is one of the limiting or regulating links in energy metabolism determining the brain's resistance to hypoxia. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 3, pp. 252–255, March, 1996.     

Effects of tissue injury mediators on thein vitro experession of surface antigens by human lymphocytes

A short-term incubation of healthy donor lymphocytes with adenosine or adenosine diphosphoric acid was shown to reduce the number of cells expressing CD4 antigen and to increase the number of CD8⁺ lymphocytes. The hydra peptide morphogen shifts the balance of immunoregulatory lymphocytes toward a predominance of CD4⁺ cells. A hypothesis of a two-level system for the regulation of surface antigen expression by lymphocytes during exposure to extreme factors is proposed. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, No. 2, pp. 196–199, February, 1995 Presented by V. N. Yarygin. Member of the Russian Academy of Medical Sciences