The alteration of attractiveness of intact males mice to females chemosignals, subjected of ionizing radiation in sublethal dose

After irradiation in a dose 4 Gy female mice of CBA and C57Bl/6 (female CBA during 18-23 days, female C57Bl/6 - 4-10 days) secretes with urine volatile components (chemosignals) which possess higher, than secretes intact females, attractiveness for intact males the same strains irrespective of a genotype. When estimation relative attractiveness postradiation secretes female mice CBA and C57Bl/6 intact males prefer chemosignals singenic (genetically identical) females during 1-23 day after irradiation. Observed olfactorial reaction male mice more differ from norm. In which males prefer chemosignals of allogenic (with a strange genotype) females. This disturbances identifed as postradiation reversion attractiving males of chemosignals, dependent on the genotype of females. Typical for norm chemosignalisation at females restored for 43 days after the irradiation. The mechanism and biological advisability of this phenomenon are discussed.     

Influence of the irradiating on olfactory ability of male mice to distinguish chemo-signals of intact individuals

It is shown, that in early terms after irradiating of male mice of lines CBA and C57Bl/6 in a sublethal dose (4 Gy) in reaction of preference-avoiding lose olfactory ability to distinguish the genotype of flying secretions of female mice and to distinguish flying secretions of female mice from secretions of male mice. Irradiated male mice not only preserve, but also raise the attractiveness to chemosignals of syngenetic intact male mice.     

Effect of natural and postradiation volatile secretions of mice on the immune reactivity and blood cellularity of irradiated animals

It has been shown that natural and postradiation volatile urinary secretions of mice can remotely restore the immune reactivity and blood indices reduced as a result of exposure of laboratory mice to ionizing radiation. Antibody formation in spleen of gamma-irradiated (1 Gy) CBA strain mice was increased after exposure of both syngeneic and allogeneic animals with urine volatile secretions. Volatile natural secretions of intact mice have a more pronounced antibody stimulating activity than volatile secretions from animals exposed to gamma-radiation. Immunoreactivity ofy-irradiated C57B16 strain mice with low olfactory reactivity increases only after their exposure with volatile secretions of intact syngeneic animals. The total number of leukocytes and lymphocytes in the peripheral blood of gamma-irradiated (1 Gy) inbred mice increases after exposure with secretions obtained from them before irradiation. The role of hemo-signalling in the selective stimulation of immunity and blood content in conditions of radiation damage is discussed.     

Syngeneic and allogeneic immunosupression effects of post-irradiation volatile excretions of mice

It was shown that immune and olfactory highly reactive CBA mice have reduced the ability to immune response in more extent under influence of volatile excretions of irradiated (4 Gy) singene mice, than allogene (C57Bl/6) mice. In lowreactive C57BL/6 mice deterioration of immune response also took place after influence of excretions of singene irradiated mice. There were no difference between the effects caused by excretions of intact and irradiated allogene (CBA) mice.     

Postradiation volatile secretion and development of immunosupression effectes by laboratory mice with various genotype

The appearance of lines CBA and C57Bl/6 in the urine of mice irradiation volatile excretions with immunosupression property was associated with the violation at mice of ability to immunogenesis. It was established, that immunosupression activity of excretions irradiated mice CBA and C57Bl/6 did not depend on genotip of mice. However, by irradiated mice C57Bl/6 immunosupression components, depressing antibody formation at intact mice, appeared earlier, than at CBA. Immunosypression, limited postradiation volatile secretion in view of depression humoral immune response at intact mice kept for not a long time and mostly expressed on the course 2-3 days after exposition with postradiation secretion.     

Immunological,Cytogenetical, and Behavioral Changes in CBA and C57BL/6 Male Mice after Pheromonal Action

Immunological and cytogenetical changes were studied in mice-recipients of CBA and C57BL/6 lines as well as modifications of their behavior appearing as a result of action of various stressors. Post-stress volatile excretions of CBA males cause led to a pronounced immunosuppression in males-recipients of both lines. This resulted in a decrease of capability for immune response of the stressed mice to sheep erythrocytes. Besides, in young males of the CBA line, frequency of chromosome aberrations in bone marrow cells increased statistically significantly after stressing by syngenec volatile excretions of mature animals. Attractive properties of volatile excretions of the CBA and C57BL/6 line males were studied. In norm, animals of both lines prefer syngenic odors of intact males donors. However, for the CBA line males, post-stress excretions from males-donors of both lines became more attractive than excretions from intact animals. Also revealed were interline differences in incidence of choice of syngenic and allogenic post-stress excretions. This can be explained both by different stress-reactivity of animals-donors and differences of recipients of the studied genotypes in selectivity to olfactory stimuli. An importance of olfactory stresses and of the revealed interline differences for explanation of some micro-and macroevolutionary synecological processes in the domestic mouse is discussed.     

Cross-Fostering of Male Mice Subtly Affects Female Olfactory Preferences

The maternal environment has been shown to influence female olfactory preferences through early chemosensory experience. However, little is known about the influence of the maternal environment on chemosignals. In this study, we used two inbred mouse strains, C57BL/6 (C57) and BALB/c (BALB), and explored whether adoption could alter male chemosignals and thus influence female olfactory preferences. In Experiment 1, C57 pups were placed with BALB dams. Adult BALB females then served as the subjects in binary choice tests between paired male urine odours (BALB vs. C57, BALB vs. adopted C57 and C57 vs. adopted C57). In Experiment 2, BALB pups were placed with C57 dams, and C57 females served as the subjects in binary choice tests between paired male urine odours (C57 vs. BALB, C57 vs. adopted BALB, and BALB vs. adopted BALB). In both experiments, we found that females preferred the urine of males from different genetic backgrounds, suggesting that female olfactory preferences may be driven by genetic compatibility. Cross-fostering had subtle effects on female olfactory preferences. Although the females showed no preference between the urine odours of adopted and non-adopted males of the other strain, the BALB females preferred the urine odour of BALB males to that of adopted C57 males, whereas the C57 females showed no preference between the urine odour of C57 and adopted BALB males. Using gas chromatography-mass spectrometry (GC-MS) and stepwise discriminant analysis, we found that the ratios of volatile chemicals from urine and preputial gland secretions were altered in the fostered male mice; these changes may have resulted in the behavioural changes observed in the females. Overall, the results suggest that female mice prefer urine odours from males with different genetic backgrounds; this preference may be driven by genetic compatibility. The early maternal environment influences the chemosignals of males and thus may influence the olfactory preferences of females. Our study provides additional evidence in support of genotype-dependent maternal influences on phenotypic variability in adulthood.     

Mechanism of the intensification of the immune response to Staphylococcus in mice after the transplantation of primed donor splenocytes

Experiments on CBA, C57Bl/6 mice and (CBA X X C57Bl/6)F1 hybrids were made to study the mechanism of stimulation of the immune response to staphylococci after injection of primed splenocytes. The stimulating action of immune splenocytes was reversed after their in-vitro treatment with anti-immunoglobulin serum and complement. The stimulant effect was also seen in a semi-allogeneic system (adoptive transfer of CBA mice immune cells to (CBA X C57Bl/6)F1 recipients). Preincubation of splenocytes with CBA-anti-C57Bl/6-serum and complement prior to demonstration of antibody-forming cells did not influence their number in the spleen of hybrid recipients injected with immune cells carrying parent genotype but decreased this indicator of the immune response in control mice. It is concluded that stimulation of the immune response to staphylococci after transplantation of primed splenocytes is due to the anamnestic response of donor's cells repeatedly stimulated by antigen in the recipient's host.     

Effects of syngeneic UV-irradiated blood transfusion on the hemopoietic function of the bone marrow in normal state and in craniocerebral injuries in mice

Experiments on mice (CBA X C57 Bl6)F1 using endo- and exogenous cloning have shown that ultraviolet irradiation of blood enhances colony stimulating properties of plasma. Stimulation of colony formation occurs both in vitro, on direct contact of UV-irradiated blood plasma with bone marrow cells, and in vivo, upon this injection to the whole organism. In the latter case, increased migration of colony forming hematopoietic cells from the bone marrow can be noted. Single intravenous injection of syngenic UV-irradiated blood prevents inhibition of hematopoietic function of the bone marrow induced by closed brain injury.     

Radiation-induced pulmonary endothelial dysfunction and hydroxyproline accumulation in four strains of mice

C57BL mice exposed to 14 Gy of whole-thorax irradiation develop significant histologic lung fibrosis within 52 weeks, whereas CBA and C3H mice do not exhibit substantial fibrosis during this time. The purpose of the present study was to determine whether this strain-dependent difference in radiation histopathology is associated with genetic differences in pulmonary endothelial metabolic activity or in endothelial radioresponsiveness. C57BL/6J, C57BL/10J, CBA/J, and C3H/HeJ mice were sacrificed 12 weeks after exposure to 0 or 14 Gy of 300-kV X rays to the whole thorax. Lung angiotensin converting enzyme (ACE) activity and plasminogen activator (PLA) activity were measured as indices of pulmonary endothelial function; and lung hydroxyproline (HP) content served as an index of pulmonary fibrosis. Lung ACE and PLA activities in sham-irradiated C57BL/6J and CB57BL/10J mice were only half as high as those in sham-irradiated CBA/J and C3H/HeJ mice. Exposure to 14 Gy of X rays produced a slight but nonsignificant reduction in lung ACE and PLA activity in the C57BL strains, and a significant reduction in the CBA/J and C3H/HeJ mice. Even after 14 Gy, however, lung ACE and PLA activities in CBA/J and C3H/HeJ mice were higher than those in sham-irradiated C57BL/6J and C57BL/10J mice. Lung HP content in all four strains increased significantly after irradiation, but this increase was accompanied by an increase in lung wet weight. As a result, HP concentration (per milligram wet weight) remained constant or increased slightly in both C57BL strains and actually decreased in the CBA/J and C3H/HeJ mice. These data demonstrate significant genetic differences in both intrinsic pulmonary endothelial enzyme activity and endothelial radioresponsiveness among the four strains of mice. Specifically, strains prone to radiation-induced pulmonary fibrosis (C57BL/6J, C57BL/10J) exhibit only half as much lung ACE and PLA activity as do strains resistant to fibrosis (CBA and C3H).     

The characteristics of the manifestation of hereditarily induced anxiety in male C57Bl/6J and CBA/Lac mice

Behavior of male mice of C57Bl/6J and CBA/Lac strains was tested in the elevated plus-maze and open field in order to estimate state anxiety in novel conditions. The cube and partition tests were used to reveal trait anxiety in the familiar conditions of the home cage. It is concluded that genetically defined state anxiety is more pronounced in CBA/Lac mice and trait anxiety in C57Bl/6J strain.     

The balance hypothesis of the effect of socially important volatile chemosignals on reactivity of chromosome machinery of bone marrow dividing cells in the house mouse <Emphasis Type="Italic">Mus musculus</Emphasis>

Volatile chemosignals released by female CBA mice are shown to affect the chromosome machinery of bone marrow cells in mature syngenic males in different ways depending on the experimental conditions. Chemosignals excreted by solitary adult females decrease the frequency of mitotic disturbances in bone marrow dividing cells of male recipients as compared with the spontaneous level in control animals. At the same time, 2,5-dimethylpyrazine, a pheromone released only by females caged at high densities, increases the frequency of mitotic disturbances. A preliminary 24-h treatment of males with chemosignals excreted by solitary females reduces the effect of a subsequent exposure to 2,5-dimethylpyrazine, however, the frequency of disturbances is still higher than that in the control. The simultaneous exposure to both chemosignals results in complete neutralization of the 2,5-dimethylpyrazine effect, and the frequency of mitotic disturbances does not differ from that observed after the exposure to solitary female chemosignals. It is hypothesized that the cytogenetic effects found in male recipients depend on the social housing conditions under which female chemosignal donors were kept.     

The effect of combined application of quercetin and indralin on postradiation repair of the hematopoietic system in acute radiation sickness

Hybrid F1 mice (CBA × C57Bl/6) were subjected to irradiation at a nonlethal dose of 6.7 Gy that brought on acute radiation sickness. In the experiments performed, we observed the beneficial effect of combined application of quercetin injected 30–60 min prior to irradiation with γ rays and the emergent radioprotector indralin injected after irradiation on development of postradiation repair in hematopoietic tissue. This effect was expressed as accelerated formation of endogenous spleen colonies and recovery of spleen weight and attenuation of leucopenia 12 and 16 days after acute irradiation. Treatment with only quercetin was not radioprotective.     

Sex difference in attraction thresholds for volatile odors from male and estrous female mouse urine

Volatile urinary odors from opposite sex conspecifics contribute to mate recognition in numerous mammalian species, including mice. We used a simple habituation/dishabituation testing procedure to ask whether the capacity to detect and investigate decreasing concentrations of volatile urinary odors is sexually differentiated in mice. Beginning 2 months after gonadectomy and in the absence of any sex steroid treatment, adult, sexually naive male and female CBA x C57Bl/6 F1 hybrid mice received two series of daily tests that involved the presentation of different dilutions of urine from C57Bl/6 males followed by urine from estrous females. Each test session began with three consecutive presentations of deionized water (10 microl on filter paper for 2 min, behind a mesh barrier which prevented direct physical access, in the home cage at 1-min intervals) followed by three presentations of one of five different dilutions of urine (a different dilution on each test day). Males and females showed equivalent, significant habituation/dishabituation responses (low investigation times for successive water presentations; increased investigation of the first urine stimulus, followed by a decline in successive urine investigation times) to both male and female urine/water dilutions of 1:1, 1:10, and 1:20. However, only female mice responded reliably to 1:40 and 1:80 dilutions of both types of urine, pointing to a sex dimorphism in the detection and/or processing of biologically relevant, volatile urinary odors by the main olfactory system.     

Influence of the maternal effect on allogenic inhibition of hematopoietic stem cells]

Bone marrow cells (0,5-10(6)) of female mice of CBA or C57BL strains were injected intravenously to lethally irradiated CBA, C57BL/6, (femaleCBA X maleC57BL/6)F1 and (femaleC57BL/6 X maleCBA)F1 mice. Spleen of recipients as assayed for colony count on the 9th day after bone marrow transplantation by the method of Till and McCullouch. Stem cells of CBA mice demonstrated failure of allogenic inhibition in (CBA X C57BL/6)F1 hybrid mice and formed the same number of colonies as in the spleen of syngenic recipients. The level of allogenic inhibition of CBA stem cells transplanted to (C57BL/6 X X CBA)F1 hybrid mice was 50%. Bone marrow cells of C57BL/6 mice formed colonies in spleen of (CBA X C57BL/6)F1 mice at least in 20 times less than in syngenic combination. In the transplantation of bone marrow from C57BL/6 mice to (C57BL/6 X CBA)F1 hybrid mice the allogenic inhibition was less pronounced (77-85%) as compared with the transfer of cells to (CBA X C57BL/6)F1 hybrid mice (95%). The sex of a recipient did not influence the number of formed colonies. The different level of allogenic inhibition of parental stem cells can not be explained by the effect of linkage with sex as the female of reciprocal hybrid mice have identical structure of sex chromosomes (X(CBA)XC57BL/6). The data obtained indicate that the maternal effect affects allogenic inhibition of stem cells in parent--F1 system. It is possible that the maternal influence may be determined by cytoplasmic factors of inheritance which affect the expressivity of recessive genes Hh, controlling the inheritance of specific haematopoietic cell antigens.     

Comparative characteristics of the parameters of an aggressive reaction in 2 mouse genotypes

The parameters have been studied of the aggressive reaction of male mice of CBA/Lac and C57BL/6J lines differing by olfactory sensitivity to zoosocial pheromone stimuli. It has been shown that CBA males, characterized by a high olfactory sensitivity, have lower latency of the first attack than C57BL males with low olfactory sensitivity. A prolonged distant exposition to an unknown litter and male appearance lowers the latency of the first attack in mice of the studied lines proportionally to their meanings demonstrated after short time exposition. The number of attacks and total time of attacking is considerably higher in C57BL mice during the whole test period (15 min) than in CBA mice in which aggressivity is already sharply lowered after 5 min of agonistic interactions. The factors are discussed, influencing the parameters of mice aggressive reaction.     

Exploratory activity of mice of different genetic strains after olfaction disruption by 3-methylindole (skatole)

The behavior of mice of two inbred strains (C57BL/6J and CBA) and their F1 hybrids was evaluated in the open field test after intraperitoneal administration of 3-methylindole (skatole) disrupting epithelium of the main olfactory system. High motor and exploratory activities and emotional sensitivity was observed in intact C57BL/6J mice compared to CBA mice and their hybrids. Anosmia induced by intraperitoneal administration of skatole changed the behavior of C57BL/6J and CBA mice. The direction of the observed changes in the orientation and exploratory behavior of anosmic animals was different. Anosmia decreased motor and exploratory activities in C57BL/6J mice and increase them in CBA mice. Intact hybrid mice demonstrated the predominance of the CBA genotype in the orientation and exploratory activity in the test used. Anosmia in hybrid animals had no significant effect on the orientation and exploratory behavior.     

Study of immunoregulating properties of an interferon inducer in animals with various reactions to the antigen

Influence of dsRNA isolated from killer yeast of S. cerevisiae on humoral and cellular immune responses in mice CBA/CaY and C57Bl/6Y with opposing reaction to the antigen was studied. It was shown that after administration of the yeast dsRNA preparation to the animals simultaneously with the antigen there was an increase in the number of the antibody forming cells in the spleen and the titer of hemolytic antibodies in blood serum of the animals with high and low reactions to the antigen. After sensitization with different doses of sheep red blood cells (10(7) and 10(8)) the preparation had immunomodulating action on development of DTH in mice CBA/CaY. The effect of the dsRNA preparation on the immunity system depended on the preparation dose, antigen loading and animal genotype and was the most marked in mice CBA/CaY with interferon levels in blood serum 2-3 times higher than those in mice C57Bl/6Y.     

Allogenic inhibition of the stem hematopoietic cells in the bone marrow of adult mice and in the embryonal liver]

The maternal effect was shown to influence the degree of allogenic inhibition of stem hemopoietic cells of the embryonic liver and adult bone marrow in CBA and C57Bl/6 mice. The display of allogenic inhibition of stem cells of the embryonic liver and adult bone marrow proved to be similar in C57Bl/6 mice and dissimilar in CBA.     

The anti-infective action of immunoglobulins administered at delayed times after irradiation

In experiments with CBA and CBA X C57Bl(F-1) mice it was shown that the radio-protective efficacy and the anti-infectious influence of homo- and heterologous immunoglobulin (IG) applied one, two and three times in the period from 4h to 9 days following irradiation with doses of LD80-95/30. This was displayed by the increased survival rate and normalization of intestinal microflora in treated animals in comparison with untreated ones. Heterologous IG administered at varying times (5 to 20 days) after irradiation with the dose of 4.8 Gy increased the resistance of treated mice to infection with living E. coli culture.