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.     

Effect of cyclic AMP on cells of experimental lymphatic leukemia L-5718

The effect of cyclic AMP (cAMP), dibutyryl-cAMP, and theophylline (an inhibitor of phosphodiesterase, the enzyme converting adenosine-3, 5-monophosphate into adenosine-5-monophosphate) on the intensity of proliferation (as reflected in the increase in the nucleic acid content in the culture), DNA synthesis (thymidine-H³ incorporation), and transplantation properties (ability to repopulatein vivo) of leukemic cells of strain L-5178 was studied. The experiments showed that cAMP in a concentration of 0.8 mM inhibits thymidine-H³ incorporation considerably, retards proliferation, and reduces the transplantability of the leukemic cells. Theophylline and dibutyryl-cAMP have comparatively weak ability to inhibit DNA synthesis and the proliferative activity and transplantation properties of the cells.Laboratory of Biochemistry and Laboratory of Experimental Therapy of Leukemias, Central Institute of Hematology and Blood Transfusion, Ministry of Health of the USSR. Laboratory for the Search for New Antibiotics, All-Union Research Institute for the Search for New Antibiotics, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR K. V. Bunin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 3, pp. 365–367, March, 1976.     

Transformation of substrate specificity of EcoRl restrictase by glycerol

In the presence of glycerol, EcoRl restriction endonuclease hydrolyzes DNA into a larger number of fragments than under ordinary conditions. On the addition of glycerol to 50% concentration, this enzyme begins to act by what is called the EcoRl' type of restriction, which was producible experimentally only by reducing the ionic strength and increasing the pH of the solution. However, under these extremal conditions, the enzyme is quickly inactivated and does not give reproducible results, especially during the hydrolysis of high-molecular-weight DNA. The conditions found for manifestation of EcoRl' activity yield reproductible results, which is essentially equivalent to the discovery of a new restriction endonuclease.The nomenclature of the restriction enzymes follows that of Smith and Nathans [6].Laboratory of Biochemistry, D. I. Inanovskii Institute of Virology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR S. S. Debov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 7, pp. 46–48, July, 1977.     

Analysis of the effect of morphine and trimeperidine on the uptake and liberation of noradrenalin by myocardial tissue

The effect of morphine and trimeperidine on the concentration, uptake, and liberation of noradrenalin (NA) in the rat myocardium was investigated. Trimeperidine lowers the NA level in the myocardium. Morphine does not affect the liberation of NA-¹⁴C from the isolated perfused heart, whereas trimeperidine significantly increases it, affecting both the slow and the rapid release of the mediator. Trimeperidine does not affect the uptake of NA-¹⁴C by the perfused heart but morphine significantly lowers it. Competition between morphine and NA is characterized by an incomplete inhibition effect: Morphine and NA mutually affect the affinity of each other for the receptor and their interaction depends on their relative concentrations.Laboratory of Pharmacology of the Cardiovascular System, Institute of Pharmacology, Academy of Medical Sciences of the USSR, Moscow. (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. 11, pp. 1345–1347, November, 1976.     

Role of injury in the appearance of “activated” smooth muscle cells

In experiments on rats the ultrastructure of the muscle tissue of the inferior vena cava after disturbance of the outflow of blood, of the muscular coat of the stomach after resection of 50% of its fundus, and of the muscular coat of the cecum after constriction of its ascending portion was studied. Activation of smooth muscles was shown to reflect the phase of injury to the ultrastructure of the cells, followed by processes of intracellular regeneration. Analysis of the ratio between DNA-synthesizing and activated cells showed the local origin of the latter from differentiated myocytes.Institute of General Pathology and Pathological Physiology, Academy of Medical Sciences of the USSR. No. 4 Main Board, Ministry of Health of the USSR. 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. 7, pp. 112–115, July, 1977.     

Synthesis of α-fetoproteinin vitro by human hepatocytes,singly and in microcolonies

By a combination of microelectrophoresis and precipitation in polyacrylamide gel, -fetoprotein (-FP) produced by single hepatocytes and by microcolonies of hepatocytes was determined. Liver cells from 6–13-week-old human fetuses were cultivatedin vitro for 2–5 days. -FP was found to be produced in amounts of between 70 and 800 pg per cell by 23 of 28 single hepatocytes and by 89 of 91 microcolonies consisting of 2 to 35 cellsLaboratory of Immunochemistry and Diagnosis of Tumors, N. F. Gamaleya Institute of Epidemiology and Microbiology, Academy of Medical Sciences of the USSR. Laboratory of Human Cytogenetics, Institute of Medical Genetics, 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. 4, pp. 481–484, April, 1977.     

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.     

Changes in 3β-OH-steroid dehydrogenase activity in the adrenals of rat fetuses decapitatedin utero

Activity of 3-OH-steroid dehydrogenase in the adrenal cortex of 21-day rat fetuses in the control and 3 days after decapitationin utero was estimated quantitatively by microspectrophotometry. Activity of the enzyme, calculated per conventional cell in the zona fasciculata was considerably higher than in the developing zona glomerulosa. After hypophysectomy the 3-OH-steroid dehydrogenase activity was reduced in both zones of the adrenal.Laboratory of Hormonal Regulation and Laboratory of Cytology, Institute of Developmental Biology, Academy of 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. 82, No. 11, pp. 1317–1320, November, 1976.     

Inhibition of passive cutaneous anaphylaxis by dipeptides

The action of certain dipeptides (L-alanyl-histidine, L-alanyl-histidine, histidyl-leucine, and glycyl-L-histidine) and of histidine itself on passive cutaneous anaphylaxis was studied in guinea pigs. L-alanylhistidine (carnosine) and L-alanyl-histidine were found to inhibit passive cutaneous anaphylaxis. Histidyl-leucine, glycyl-histidine, and histidine had no inhibitory action on passive cutaneous anaphylaxis.Allergologic Research Laboratory, Academy of Medical Sciences of the USSR, Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 10, pp. 460–462, October, 1977.     

Electron-microscopic study of interaction between cytolytic T lymphocytes and target cells

Thymocytes stimulatedin vitro in mixed culture were adsorbed by centrifugation on to the surface of target cells for an electron-microscopic study of the cytology of immune T lymphocytes and of the early stages of cytolysis. A well-developed Golgi apparatus and clusters of tubular structures 50–60 nm in diameter, communicating with the cisternae of the granular endoplasmic reticulum, with emptied vesicles, and with the plasma membrane of the lymphocyte, were found in the cytoplasm of the lymphocytes. Over a wide area the plasma membrane formed numerous contacts with the membrane of the target cells, so that closed slit-like spaces were formed. With these data and also modern views regarding interconversion of membranes and intracellular transport in mind, a hypothetical scheme for the mechanism of cytolysis of the target cell by the immune T lymphocyte is suggested.Oncologic Scientific Center, Academy of Medical Sciences of the USSR, Moscow. 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 O. V. Baroyan.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 10, pp. 443–447, October, 1977.     

Localization of albumin,transferrin, andα-fetoprotein in normal and regenerating mouse liver

A technique of tissue fixation with a mixture of acetone and formalin followed by embedding in paraffin wax, enabling good detection of antigens, including serum proteins, is described. By means of this method the distribution of albumin, transferrin, and-fetoprotein was described in normal and regenerating mouse liver. Both under normal conditions and during regeneration albumin and transferrin are contained by strictly the same hepatocytes.-Fetoprotein is found in the regenerating liver independently of the other two proteins, although it is found in the same zones. Albumin and transferrin are found only in the perinecrotic zone in each cell containing-fetoprotein.Laboratory of Immunochemistry and Diagnosis of Tumors, 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. 85, No. 5, pp. 626–630, May, 1978.     

Mechanism of action of nonachlazine on nervous control over the coronary circulation

The new antiaginal drug nonachlazine, in experiments on anesthetized cats and dogs, inhibited the response of reflex decrease of the blood flow into the coronary arteries. In freely behaving cats nonachlazine also inhibited reflex changes in the blood flow in the system of the common carotid artery and reduced pressor vasomotor reflexes. Nonachlazine selectively inhibited vasoconstrictor impulses from A-afferent fibers of spinal nerves, i.e., it acts on the vasomotor component of the primary nociceptive response. This mechanism may perhaps lie at the basis of the relief of the pain syndrome by nonachlazine in ischemic heart disease.Laboratory of Pharmacology of the Cardiovascular System, Institute of Pharmacology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Zakusov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 3, pp. 319–322, March, 1976.     

Characteristics of hepatocytes containing α-fetoprotein in regenerating mouse liver

After poisoning SWR mice of different ages with single or repeated doses of CCl₄ vapor the synthesis of the embryo-specific protein -fetoprotein (-FP) was induced. The greatest rise in the -FP level was observed in mice under 1 month old. In sections through the liver regenerating after CCl₄ poisoning, -FP was found in hepatocytes indistinguishable from the main population: in small cells in young animals and in large, polyploid hepatocytes in the repeatedly poisoned mice. The only distinguishing feature of the -FP-containing cells after poisoning of the mice with different doses of CCl₄ was that most of them were on the boundary with the necrotic zone. A similar localization of -FP-containing hepatocytes was observed when two other hepatotoxins were used: paracetamol and allyl alcohol.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 P. A. Vershilova.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 7, pp. 97–101, July, 1977.     

“Exercise pyrogens”

Blood plasma taken from subjects either at rest or during muscular exercise was injected intravenously into rabbits. The rectal temperature of the animals changed differently: After injection of exercise plasma the temperature was at a higher level. This effect can be explained by the presence of exercise pyrogens in the plasma.Department of Physiology, Moscow Regional Institute of Physical Culture, Malakhova, Moscow Province. (Presented by Academician of the Academy of Medical Sciences of the USSR V. A. Negovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 8, pp. 144–145, August, 1979.     

Heterogenous antigens in vaccine preparations ofVibrio cholerae

Serological similarity was found between antigens of the human small intestine, stomach, and liver and antigens of various fractions of cholera vibrios. An antigenic similarity was found on testing the heart and kidney. Heterogenous antigen was found not only in somatic antigen ofV. cholerae strain 569 (B), but also in the cholerogen, the toxoid which is the most widely used prophylactic preparation in use at the present time, obtained from it.Mikrob Plague Research Institute, Ministry of Health of the USSR. Research Laboratory of Experimental Immunobiology, Academy of Medical Sciences of the USSR, Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 8, pp. 961–962, August, 1976.     

Quantitative analysis of stimulation frequency transformation in the neuromuscular apparatus

The dependence of the parameters of neuromuscular transmission on the frequency of stimulation was determined. This dependence was analyzed in relation to fatigue of the synapse arising during prolonged repetitive stimulation of muscle. The proposed mathematical model and the method of statistical analysis of the records of evoked responses of the muscle derived from it permit approximate estimates to be made from the experimental data of parameters quantitatively reflecting frequency (transmission) properties of the neuromuscular apparatus.Laboratory of Mathematical Modeling and Processing of Experimental Data, Institute of General Pathology and Pathophysiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. M. Chernukh.) Translated from Byullten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 8, pp. 1016–1018, August, 1976.     

Foraging strategies ofDrosophila melanogaster: A chromosomal analysis

Two larval foraging strategies inDrosophila melanogaster were identified, rover and sitter. Rovers traverse a large area while feeding whereas sitters cover a small area. The difference between rovers and sitters was analyzed genetically by chromosomal substitutions between isogenic stocks. Differences in larval locomotor behavior (crawling behavior) can be attributed to the second chromosome, the rover strategy being dominant over the sitter strategy. Differences in feeding rate (shoveling behavior) are affected additively by both the second and third chromosomes. Natural populations ofDrosophila larvae were sampled three times over a 2-month period; rovers and sitters were at constant frequencies in these populations. The two foraging strategies are discussed in the light of resource utilization in environments where food is distributed continuously or discontinuously.     

Potentiation of the effect of L-dopa by α-methyldopa

After preliminary administration of -methyldopa to mice, the stereotypes induced by L-dopa were potentiated and prolonged. The ability of L-dopa to abolish catalepsy induced by reserpine and haloperidol also was potentiated. In cats, -methyldopa potentiated the responses of the arterial blood pressure and contractions of the nictitating membrane induced by L-dopa and dopamine, if the interval between injection of the substances was 4–6 h.Department of Pharmacology, Faculties of Internal Medicine and Preventive Medicine, I. M. Sechenov First Moscow Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Zakusov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 3, pp. 314–316, March, 1976.     

Immunogenicity of polymers of H antigen obtained by different methods

The properties of two polymers obtained from flagellin by different methods — precipitation by ammonium sulfate followed by centrifugation or treatment with glutaraldehyde in solution followed by gel chromatography — were studied. Molecules of the former (POL) and the latter (GLUT) are similar in shape but POL has a higher molecular weight. The preparations contain a common H antigen and are similar in serologic activity. POL has very high priming activity for mice. GLUT is highly immunogenic only within a narrow dose range, is less immunogenic than POL, and differs from POL in forming a certain quantity of 7S antibodies.Department of Chemotherapy, All-Union Research Institute for the Search for New Antibiotics, Academy of Medical Sciences of the USSR. Department of Physical and Chemical Methods of Investigation, I. I. Mechanikov Moscow Research Institute of Vaccines and Sera, Ministry of Health of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR G. F. Gauze.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 5, pp. 551–554, May, 1978.     

Activation of precursors of T killers of hematopoietic stem cells by thymosine

Lymph node cells from normal CBA mice, from CBACBA syngeneic radiation chimeras, and B mice were incubatedin vitro with fraction 5 of thymosine, and transplanted into sublethally irradiated (CBA x C57BL)F₁ recipients, and the number of endogenous colonies in the recipients' spleen was determined. Thymosine was shown to potentiate the killer activity of lymph node cells of normal CBA mice and of CBACBA syngeneic radiation chimeras, but not of B mice. It is suggested that the target for the action of thymosine is the subpopulation of T₁ lymphocytes.Academician of the Academy of Sciences of the USSR.Institute of Biophysics, Ministry of Health of the USSR, Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 5, pp. 602–605, May, 1978.