Changes in the level of epidermal G2 chalone and mitotic activity in the vaginal epithelium of rats

The content of epidermal inhibitor of mitosis (G₂ chalone) at different stages of the estrous cycle in rats was determined by the radial immunodiffusion method. The chalone level correlates with the mitotic index of the vaginal mucous membrane and is minimal in proestrus and maximal in estrus. In aging (14–16 months) rats with regular cycles the content of G₂ chalone in the vaginal mucous membrane at all phases of the estrous cycle was significantly lower than in young (3–4 months) rats with a regular cycle. In castrated rats the mitotic index begins to rise 18 h after a single injection of estradiol benzoate (1 g/100 g body weight). This increase is preceded by a significant decrease in the concentration of G₂ chalone 12 h after injection of the estrogen.Laboratory of Experimental Tumors and Laboratory of Endocrinology, N. N. Petrov Research Institute of Oncology, Ministry of Health of the USSR, Leningrad. (Presented by Academician of the Academy of Medical Sciences of the USSR A. I. Serebrov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 87, No. 4 pp. 349–351, April, 1979.     

Effect of the normal microflora and age and sex of rats on the serum IgG2 level

Germfree and ordinary rats, bred in the laboratory, and rats obtained from nurseries were used. IgG₂ was isolated from the serum of noninbred rats and a rabbit antiserum against it obtained. By radial immunodiffusion the quantity of this immunoglobulin was determined in the blood serum of different groups of animals. The IgG₂ content in germfree rats of the Fisher strain was only 19% of that in animals of this strain obtained from the nursery, and in females it was 10–15% higher than in males. The IgG₂ level in newborn rats within a few hours after birth was identical regardless of its concentration in the maternal blood serum. The results may be used as standards for various immunological experiments on rats.Laboratory of Gnotobiology, N. F. Gamaleya Institute of Epidemiology and Microbiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR P. A. Vershilova.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 86, No. 9, pp. 335–337, September, 1978.     

Cyclic AMP formation during phagocytosis

The content of cyclic adenosine-3, 5-monophosphate (AMP) in phagocytic macrophages was shown to be increased especially during phagocytosis of the living microbes. The cyclic AMP formed during phagocytosis could be detected in the incubation medium, but in the cells it remained at almost the same level. The cyclic AMP concentration in cells of the intestinal mucosa and in the blood serum of germfree guinea pigs also was increased after injection ofEscherichia coli 055 cells; this points to the participation of the adenylate cyclase system in interaction between microorganisms and the epithelium of the small intestine.Research Laboratory of Experimental Biological Models, Academy of Medical Sciences of the USSR. Institute of Biological and Medical Chemistry, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR, V. N. Orekhovich.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 8, pp. 953–956, August, 1976.     

Blocking factor of normal animal serum inhibiting immunological responses in vitro

The sera of Wistar and noninbred rats of different ages and sexes were found to contain an extremely thermostable factor, resistant to various chemicals, which inhibits the action of normal and immune antibodies against the red blood cells and serum antigens of rats. The blocking factor is relatively species specific and is more active in respect of the action of normal than of immune antibodies. The activity of the blocking factor is connected with ₁-globulin.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. 80, No. 11, pp. 70–73, November, 1975.     

Changes in the blood serum protein spectrum of mice after injection of a globulin preparation containing homologous tissue antibodies

The blood serum protein spectrum of mice differing in their initial resistance to malignant tumors was investigated by disc electrophoresis in polyacrylamide gel. Differences between different strains of mice were found in the zone containing immunoglobulins. The injection of a globulin preparation containing a high titer of normal tissue antibodies induced an increase in ₂-macroglobulin and ₁-lipoprotein, containing mainly IgM and also a certain quantity of IgG, in mice of the two lines tested.Laboratory of Pathological Physiology, P. A. Gertsen Moscow Oncologic Scientific-Research Institute. Institute of Biophysics, Ministry of Health 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. 88, No. 8, pp. 177–179, August, 1979.     

Pattern of transplacental penetration of 7,12-dimethylbenz(a)anthracene and its distribution in the fetal organs in man

On the 21st day of pregnancy 7,12-dimethylbenz(a)anthracene (DMBA) was injected into female rats in a dose of 15 mg/kg and its concentration in the liver of the pregnant rats, the placenta, and the fetus was determined by a fluorescence-spectral method. The maximal concentration was rapidly reached (after 10–15 min) in the liver of the pregnant rats (45 mg/kg) and placenta (6.3 mg/kg), but more slowly (after 1 h) in the tissues of the fetus (2.4 g/kg). Clearance of the carcinogen from all the tissues took place relatively slowly (in about 5 h). DMBA was shown to be irregularly distributed in the different organs of the fetus 1 h after its injection into the pregnant rats: maximally in the fetal liver, minimally in the carcass, compared with its concentration in other organs (kidneys, lungs, brain, intestine). The results do not correlate with data showing the development of tumors predominantly in the kidneys and nervous system of rats following transplacental exposure to DMBA.Laboratory of Biophysics and Laboratory of Experimental Tumors, Professor N. N. Petrov Research Institute of Oncology, Ministry of Health of the USSR, Leningrad. (Presented by Academician of the Academy of Medical Sciences of the USSR L. M. Shabad.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol 86, No. 10, pp. 477–479, October, 1978.     

Synthesis of α-fetoprotein and albumin by human embryonic hepatocytes

Population aspects of the production of specific secreted proteins (serum albumin and -fetoprotein) were studied in cultures of hepatocytes from human embryos at 6–12 weeks of development. A method based on local hemolysis in gel using sheep's erythrocytes conjugated with antibodies against the proteins for testing, was used. The overwhelming majority of hepatocytes were shownto synthesize both proteins.Laboratory of Human Cytogenetics, Institute of Medical Genetics, Academy of Medical Sciences of the USSR. Laboratory of Immunochemistry and Diagnosis of Tumors, N. F. Gamaleya Institute of Epidemiology and Microbiology, 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. 83, No. 6, pp. 711–713, June, 1977.     

Interaction between 9, 10-dimethyl-1,2-benzanthracene and “hairy” cells in the CNS

After injection of the carcinogen 9,10-dimethyl-1,2-benzanthracene (DMBA) into the right cerebral hemisphere of rats a capsule forms around it, the first layer of which is formed by hairy cells. Two fundamentally distinct mechanisms have been distinguished in these hairy cells: simple phagocytosis and biochemical interaction between the carcinogen and membrane. It is suggested that in the latter case secondary carcinogenic products consisting of steroid hormones are formed; morphologically these can be identified with lipid-like structures of the hairy cell.Institute of Human Morphology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. P. Avtsyn.) Translated from Byulleten Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 8, pp. 197–199, August, 1977.     

β-Adrenorecptors on the surface membranes of lymphocytes and macrophages

The effect of -adrenergic stimulators adrenalin and isoproterenol and of the -adrenergic blocker propranolol on lymphocytosis and on the macrophage adhesion inhibition reaction was studied in vivo and in vitro on sensitized and intact guinea pigs and Wistar rats. Adrenalin and isoproterenol were shown to inhibit the reaction of the antigen with both sensitized and intact cells. Propranolol abolishes the protective effect of adrenalin and isoproterenol and restores the sensitivity of the cells to antigen.Research Laboratory of Experimental Immunology, 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. 85, No. 6, pp. 723–725, June, 1978.     

Immunochemical identification of a new embryonic antigen in ovarian tumor tissue

A new embryonic antigen was found in ovarian tumors by methods of immunodifusion analysis. This antigen consists of two components with different electrophoretic mobilities: The slow peak migrates in the _o-globulin zone, the fast peak in the prealbumin zone. It is immunologically different from -fetoprotein and from the carcinoembryonic antigen of the large intestine. The antigen was found in fetal and neonatal blood serum and also in, tissue extracts of ovarian tumors. It was not found in normal adult human tissues or in the blood serum of healthy donors and cancer patients.Department of Biochemistry and Problem Laboratory for Immunochemistry of Malignant and Embryonic Tissues, N. I. Pirogov Second Moscow Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR Yu. M. Lopukhin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 6, pp. 725–726, June, 1976.     

Characteristics of heterologous antisera against stromal fibroblasts

Experiments with heterologous rabbit antifibroblast sera (AFS) against guinea pig stromal mechanocytes showed that culture media from subcultured stromal mechanocytes from the bone marrow, spleen, and thymus contain a specific trypsin-resistant fibroblast protein (AG-1), which is present also in normal blood serum and on the surface of the stromal fibroblasts. AG-1 is insensitive to the action of collagenase and evidently differs from the chief surface protein (CSP) of fibroblasts. AG-1 is a ₁-globulin and is probably the hitherto unknown specific surface protein of fibroblasts. Antibodies against a nonspecific fibroblast protein (AG-2) and an ₁-globulin related to AG-1 also were found in the AFS.Laboratory of Immunomorphology, N. F. Gamaleya Institute of Epidemiology and Microbiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR P. A. Vershilova.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 86, No. 10, pp. 454–458, October, 1978.     

Mechanism of action of breakdown products of granulocytes on granulocytopoiesis

The leukopoietic activity of blood serum was studied after injection of the breakdown products of 12 and 60 million homologous granulocytes per 100 g body weight into intact Wistar rats, and the character of the action of the serum on proliferation and differentiation of hematopoietic stem cells was determined in the spleen of lethally irradiated mice. The accumulation of granulopoietins in the blood under the influence of the granulocyte breakdown products was greater after injection of material from 12 million granulocytes. Granulocytopoietins stimulate the proliferative activity of stem cells and their differentiation into granulocytes in the spleen of lethally irradiated mice. It is concluded that granulocytes breakdown products have a stimulating action on hematopoiesis through granulocytopoietins.Pathophysiological Laboratory, Central Institute of Hematology and Blood Transfusion, Ministry of Health of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Fedorov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 6, pp. 731–733, June, 1978.     

Role ofβ-adrenoreception in realization of glycogenolytic and lipolytic effects of an excess of thyroid hormones

Experiments on rats showed that chronic administration of the -adrenoblocker propranolol in doses blocking glycogenolytic and lipolytic effects of exogenous adrenalin, does not prevent the fall in the glycogen level in the liver and myocardium and the rise in the serum free fatty acid level and in the lipolytic activity of adipose tissue in vitro arising under the influence of large doses of thyroxine.Laboratory of Pathological Physiology, Institute of Experimental Endocrinology and Hormone Chemistry, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Yudaev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 12, pp. 667–669, December, 1979.     

Activity of serum lysosomal enzymes in rats with experimental lead poisoning

The effect of experimental lead poisoning on the permeability of the lysosomal membrane was investigated in albino rats. Activation of two lysosomal enzymes, -mannosidase and -acetylglucosaminidase, was found in the blood serum as early as on the third day of daily administration of lead acetate (20 mg/kg) to the rats. Innury to the lysosomal membrane evidently plays an important role in the pathogenesis of lead poisoning.Hygiene Center, Medical Academy, Sofia, Bulgaria. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Zakusov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 9, pp. 1070–1071, September, 1976.     

Effect of sex and the phase of the estrous cycle on intensity of injury and repair processes in the liver of rats with acute carbon tetrachloride poisoning

The pattern of injury and repair in the liver of Wistar rats depending on sex, the phase of the estrous cycle, and also under the conditions of deficiency of female sex hormones and after injection of -estradiol into ovariectomized rats was studied by morphometric, histo chemical, and electron-microscopic methods. Structural disturbances caused by CCl₄ were found to be increased and reparative reactions inhibited in the liver of females both during the period of a natural increase in the blood estrogen concentration and under the influence of exogenous estradiol, and ovariectomy also had a protective effect. In males, structural changes in the liver were more marked than in females with a low blood estrogen level and differend only a little from those in females during the period of increased secretion of sex steroids.Central Research Laboratory, Novosibirsk Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. P. Kaznacheev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 4, pp. 460–464, April, 1978.     

Effect of a carcinogen on electrical activity of the rat stomach

Acute experiments on rats showed that intragastric injection of an aqueous solution of N-methyl-N-nitro-N-nitrosoguanidine (MNNG) depresses electrical activity of the stomach wall, as reflected in a decrease in the amplitude and frequency of the basic electrical rhythm and, in most cases, its total disappearance. After administration of MNNG the excitatory response of electrical activity both to electrical stimulation of the vagus nerve and to injection of carbachol disappears, but the inhibitory response both to stimulation of the vagus nerve and to injection of ATP is maintained.Department of Protective and Regulatory Mechanisms in Carcinogenesis, Institute for Problems in Oncology, Academy of Sciences of the Ukrainian SSR, Kiev. (Presented by Academician of the Academy of Medical Sciences of the USSR N. N. Gorev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 10, pp. 447–450, October, 1979.     

Effect of neuromediators on the antinociceptive effect of mesencephalic stimulation in rats

The action of L-tryptophan (25 mg/kg, intraperitoneally) and microinjection of serotonin (20 g), dopamine (10 g), and neostigmine (5 g) into the circum aqueductal gray matter on the antinociceptive effect of stimulation of the same points of the mesencephalon was studied in rats with implanted cannula-electrodes. L-tryptophan, serotonin, and neostigmine (after preliminary injection of methylatropine) potentiated the effect of subthreshold antinociceptive stimulation, tested with respect to changes in thresholds of appearance of individual components of the complex nociceptive response to electrical stimulation of the rat's tail. Dopamine did not possess this action. The potentiating effect of serotonin is not abolished by naloxone.Department of Pharmacology, First Leningrad Medical Institute. Institute of Pharmacology, Academy of Medical Sciences of the USSR, Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 11, pp. 551–553, November, 1979.     

Serum and liver cholesterol levels in experimental fever

A single intravenous injection of pyrogenal (10 g/kg) or a culture ofBacillus mesentericus (3·10⁹ bacterial cells/ml/kg body weight) lowered the total blood serum cholesterol concentration on account of its ester-bound fraction and increased both the ester-bound and the free cholesterol concentrations in the liver after 3 h. After 24 h, when the normal temperature was restored, the concentrations of cholesterol and its fractions in both the serum and liver were higher than initially.Department of Pathological Physiology, I. P. Pavlov First Leningrad Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR P. N. Veselkin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 79, No. 4, pp. 46–47, April, 1975.     

Properdin and the protein composition of the lymph and blood during resuscitation

Experiments on dogs showed that terminal blood loss followed by resuscitation by injection of autologous blood into the bone marrow causes a regular redistribution of proteins between the blood, limbs, and tissues. Retention of properdin and -globulins is observed in the interstitial tissue and is not abolished by the resuscitation measures; a stress discharge of -globulins is also found from the lymph nodes.Department of Pathological Physiology, N. P. Ogarev Mordovanian University, Saransk. (Presented by Academician of the Academy of Medical Sciences of the USSR P. D. Gorizontov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 7, pp. 24–26, July, 1977.     

Changes in myocardial reactivity in white rats to repeated injections of adrenaline

Summary Frequent injections of large doses of adrenaline in rats, resulted in myocarditis with characteristic changes of ECG only after the first injection. As the myocarditis developed into cardiosclerosis, the ECG became normal in spite of daily injections of myocarditic doses of adrenaline.The changed adrenaline response following the first injection may be regarded as an adaptive phenomenon.Submitted by Active Member of the Academy of Medical Sciences USSR V. V. Zakusov