Effect of benzo(a)pyrene on monolayer cultures of normal and malignant mouse liver cells

Cells of a monolayer culture of embryonic mouse liver, like cells of a culture of highly malignant hepatoma 22A, maintained by transplantation for 20 years, actively metabolized the carcinogenic hydrocarbon benzo(a)pyrene and are highly sensitive to its toxic action. Considering that liver tissue in vivo is resistant to carcinogenic hydrocarbons, the authors suggest that this resistance is due to factors acting at the organ or organism level but not at the cell level. The problem of the mechanism of preservation of the sensitivity of hepatoma 22A to the toxic action of benzo(a)pyrene also is discussed.Laboratory of Chemical Carcinogenesis, Oncologic Scientific Center, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR L. M. Shabad.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 9, pp. 346–349, September, 1977.     

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 endothelin-1 on DNA synthesis in the myocardium of albino rats during early postnatal ontogeny

Effect of intraperitoneal injection of endothelin-1 on DNA synthesis in the myocardium of newborn albino rats was studied by³H-thymidine autoradiography. Endothelin-1 injected in a single dose of 10 μg/kg stimulated proliferative processes: the index of labeled nuclei and labeling intensity increased. Repeated (5 times) administration of endothelin-1 in doses of 1 and 10 μg/kg increased labeling intensity, but did not change the index of labeled nuclei. The data suggest that endothelins, are involved in morphogenesis of the myocardium during the early postnatal ontogeny. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 130, No. 12, pp. 623–626, December, 2000     

Effect of calcium channel blocker verapamil on DNA synthesis and activity of nucleolar organizer in cardiomyocytes of newborn albino rats

Fivefold administration of L-type Ca²⁺ channel blocker verapamil in a dose of 1.5 mg/kg to newborn rats increased the parameters of DNA-synthetic activity in the myocardium: labeling index and intensity increased 1.24-fold on average. Body weight decreased with simultaneous increase in the absolute and relative heart weight. Morphometric parameters of the nucleus and nucleoli were practically unaffected. Our findings suggest that the Ca²⁺ channel blocker verapamil administered at the early postnatal stages can modulate morphogenesis of the heart Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 127, No. 6, pp. 658–660, June, 1999     

Effect of amniotic fluid from patients with fetal pathology (anencephaly) on cell differentiation in nervous tissue culture

The addition of amniotic fluid from pregnant women with anencephaly to neuronal and organotypic cultures initiated from germinal brain cortex of 8–12-week-old human embryos has no appreciable effect on growth and differentiation of neurons. However, it stimulates the formation of endothelial channels and affects cell-to-cell interactions. This is assumed to be a factor associated with an abnormal development of the CNS in anencephaly. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 122, No. 7, pp. 87–90, July, 1996     

Cytopathogenic action ofEscherichia coli cells containing heterologous human type O(H) antigen on human cells in culture

The character of interaction between two enteropathogenic strains ofEscherichia coli of serotype 055K59 with human HeLa cells containing O(H) isoantigen was studied. On the addition of strainE. coli No. 5789, containing heterologous type O(H) antigen to a culture of HeLa cells, a cytopathogenic action was discovered on the third day of interaction in the presence of doses of bacterial cells of 2·10¹⁰, 2·10⁵, and 2·10⁴. A dose of 2·10³ bacterial cells ofE. coli did not give this effect. Strain No. 3827, not containing heterologous antigen of ABO type, had no cytopathogenic action in maximal, average, and small doses of bacterial cells. It is suggested that the cytopathogenic action of strain No. 5789 is connected with the presence of an antigen in this strain which is identical with the group antigen of the human cell culture studied.Research Laboratory of Experimental Immunobiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of medical Sciences of the USSR N. N. Zhukov-Verezhnikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 7, pp. 70–72, July, 1977.     

Effect of polycation based on alkaloid lupinin-antihepolin and its complex with heparin on DNA synthesis in rat hepatocytes

The effect of the antiheparinate antihepolin on the intensity of replication processes in rat hepatocytes was studied. A single intravenous infusion of polycation caused an approximately 6-fold increase in the intensity DNA synthesis on day 2 postinjection followed by a drop to thebaseline level on days 5–6. If antihepolin was injected in parallel with heparin, DNA synthesis was intensified after just 24 hours. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 6, pp. 627–629, June, 1994 Presented by B. T. Velichkovskii, Member of the Russian Academy of Medical Sciences     

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     

DNA synthesis by fibroblasts of granulation tissue during stimulation of wound healing

The dynamics of DNA synthesis in fibroblasts of granulation tissue of wounds was investigated in adults mice, some of which were given potassium orotate. Regions of the wound in animals receiving 0.2 ml of a 2% solution of potassium orotate and in control animals were investigated autoradiographically daily. Under the influence of potassium orotate fibroblasts took up DNA synthesis more frequently: Increased proliferative activity of these cells was found during stimulation of wound healing.Department of Pathological Anatomy, A. V. Vishnevskii Institute of Surgery, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. V. Smol'yannikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 9, pp 352–354, September, 1977.     

Effect of sedatin,a synthetic dermorphin analog,on cell division in the corneal and lingual epithelia of rats

Sedatin, an analog of the opioid peptide dermorphin, which is a mixed μ- and δ-receptor agonist, had no effect on DNA synthesis and mitotic activity in the corneal or lingual epithelium of rats in a single dose 10 μg/kg, but stimulated cell division in both epithelia in a single dose of 100 μg/kg and in the 10 μg/kg dose administered either once daily over a 21-day period or just once after a single injection of the opiate receptor antagonist naloxone. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, No. 6, pp. 641–644, June, 1996     

Effect of low-dose gamma radiation on nuclear RNA-polymerase activity and protein synthesis in liver cells of different-age chicks

The effect of low-dose (0.05 Gy) gamma irradiation of chicks in the preincubation period on subsequent liver cell RNA-polymerase activity and protein synthesis is studied at different ages. It is shown that irradiated chicks demonstrate an increased level of RNA-polymerase and increased incorporation of labeled amino acids into cytoplasmic proteins. Apparently, low-dose ionizing radiation induces activation of the liver cell genome, this being one of the main mechanisms of the general stimulatory effect of low doses. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, No 3, pp. 286–288, March, 1995     

Acute cell death induced by inhibition of DNA synthesis in various parts of the gastrointestinal tract

Injection of hydroxyurea into mice led after 4 h to degeneration of nearly all DNA-synthesizing cells in the crypts of the small intestine, but only about 10% of these cells in the epithelium of the glandular part of the stomach underwent necrosis under these conditions. Hydroxyurea inhibited DNA synthesis equally in both tissues. The resistance of the gastric cells, as shown by the criterion of acute death, reflected their ability to with-stand inhibition of DNA synthesis without degeneration. This property is perhaps preserved in tumors of the stomach and may be one factor determining their resistance to chemotherapy.Presented by Academician of the Academy of Medical Sciences of the USSR L. M. Shabad.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 80, No. 8, pp. 33–35, August, 1975.     

Decrease in tissue-specific resistance of the gastric epithelium to acute cell death induced by inhibition of DNA synthesis

Administration of hydroxyurea to mice caused acute death of a few cells synthesizing DNA in the epithelium of the glandular stomach. If actinomycin D was given 8 h before the hydroxyurea, cell death was sharply intensified and about 80% of cells synthesizing DNA died during administration of the hydroxyurea. Administration of actinomycin D simultaneously with hydroxyurea had no potentiating effect on cell death. It is postulated that actinomycin D stimulates protein synthesis in stomach cells (the superinduction effect), thus increasing their sensitivity to inhibition of DNA synthesis.Sector of Kinetics of Chemical and Biological Processes, Institute of Chemical Physics, Academy of Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR L. M. Shabad.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 4, pp. 491–492, April, 1977.     

Effects of angiotensin II on DNA synthesis in the myocardium and epithelial tissues in newborn rats

The effects of angiotensin II on DNA synthesis in the myocardium and epithelial tissues of the skin and intestine were studied in 7-day-old albino rats by autoradiography. Angiotensin II significantly increase the labeling index of the nuclei and labeling intensity in myocardial cells and intensified cell proliferation in epithelial tissues. Thus, angiotensin II stimulates proliferative processes in the myocardium and epithelial tissues of the skin and intestine in newbown rats. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 12, pp. 643–645. December, 1998     

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 micronized fenofibrate (Lipanthyl-200M) on cholesterol synthesis in peripheral blood lymphocytes in hyperlipidemic patients with coronary heart disease

The rate of cholesterol synthesis in peripheral blood lymphocytes and plasma lipid and lipoprotein spectra are studied in patients with isolated hypercholesterolemia and combined hyperlipidemias (IIa and IIb hyperlipidemias according to Frederickson classification).¹⁴C-acetate incorporation into cholesterol in peripheral blood lymphocytes is considerably higher in patients with type IIb hyperlipidemia. Lipanthyl-200M reduces the rate of cholesterol synthesis in lymphocytes of both groups. A direct correlation is established between serum triglyceride level and the rate of cholesterol synthesis. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 125, No. 5, pp. 569–573, May, 1998     

Involvement of angiotensin II system components in regulation of DNA synthesis in pyloric epithelium of albino rats

Effects of intraperitoneal injections of angiotensin II and oral intake of cosaar (angiotensin II receptor blocker) and ednite (angiotensin-converting enzyme inhibitor) on DNA synthesis in the pyloric portion of the stomach was studied in adult albino rats by autoradiography with³H-thymidine. Proliferative processes in the studied tissue were enhanced 24 h after single injection of the peptide in a dose of 50 μg/kg and 4 h after injection of 100 μg/kg peptide. Treatment with cosaar and ednite for 2 weeks led to normalization of stress-activated epithelial proliferation in the pyloric part of the stomach. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 129, No. 2, pp. 214–216, February, 2000     

Analysis of extrachromosomal DNA from normal and tumor cells

Two independent methods (pulse-electrophoresis of intact DNA isolated from agarose-encapsulated cells and differential extraction of intact DNA from Celite-immobilized nucleoproteins) yielded evidence of the presence of free (extrachromosomal) DNA in cells of various origin, both malignant and normal, cultured and isolated from animal tissues. Free DNA from all cell types studied form three discrete electrophoretic bands of 400, 250–300, and 50 thousand base pairs. According to the data on³H-thymidine incorporation, free and chromosomal DNA differ in their metabolic properties. By means of the polymerase chain reaction using c-myc and L-myc primers it is established that free DNAs of HT1080 cells contain structural genes. Application of the method of conformational polymorphism of single-strand fragments revealed their identity to the corresponding genes localized in the chromosomes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, No 5, pp. 533–536, May, 1995 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences     

Cell-to-cell interactions in cultures of swine bone marrow cells and CPK-66b cells infected with african swine fever virus

In the presence of specific antiserum, cultured bone marrow cells from pigs infected with African swine fever virus form cell-to-cell junctions which are morphologically similar to those observed in antibody-dependent cellular cytotoxicity. This type of cytotoxicity does not determine the reaction of delayed hemadsorption, since this reaction is realized in a long-term culture of CPK-66b cells in the absence of the effectors of antibody-dependent cellular cytotoxicity. The sensitivity of delayed hemadsorption depends on the variant of infecting virus. A negative correlation is established between the area of the contact between erythrocytes and cells infected with different variants of the virus, on the one hand, and titers of antibodies in the delayed hemadsorption reaction, on the other. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 122, No. 10, pp. 418–424, October, 1996     

Effect of adrenalectomy on diurnal rhythm of number of DNA-synthesizing and dividing cells in the mouse lingual epithelium

Diurnal changes in the number of DNA-synthesizing cells and in the number of mitoses were studied in the lingual epithelium of intact and adrenalectomized mice. After adrenalectomy partial desynchronization of mitotic cell division, a decrease in the amplitude of variations in the mitotic index during the 24-h period, and lengthening of the period of increase in the number of mitoses began to occur. The mean diurnal mitotic index in the stratum basale of the lingual epithelium was the same in the control and the experimental series. The rhythm of DNA synthesis in the adrenalectomized mice was the same as in the control. Adrenalectomy thus disturbs the diurnal rhythm of the number of mitoses in the lingual epithelium but does not affect the rhythm of DNA synthesis or the level of proliferative activity.Department of General Biology and Laboratory of Chronobiology, Scientific-Research Center, N. I. Pirogov Second Moscow Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Kupriyanov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 4, pp. 479–481, April, 1977.