Problems in the genetics of stress. II. Genetic analysis of endocrine gland weight in mice under normal conditions and during exposure to stress]

Relative weight of adrenals, thymus, hypophysis and gonads was studied in female mice after 21 days after parturition and in intact males. One group of females was stressed during pregnancy, and another group was intact. All these animals were a progeny of the full diallele cross of 4 inbred mice strains (BALB/c, C3H/He, C57BL/6, AKR/J). On the basis of analysis of general and specific combining ability the conclusion is drawn that the relative weight of the endocrine glands is inherited additively in females of both experimental groups. However, it was found that the size of additive genetic variation for these characters in the population of females, which had been stressed during their pregnancy was larger, than in the control population. A significant role of non-additive genes in the determination of these characters was observed in males. The degree of hypertrophy of adrenals and lysis of thymus in stressed females corresponded to their emotional reactivity. Significant genotypic correlations between the weight of some endocrine glands, on one hand, and the emotional reactivity and the rate of sexual maturation, on the other hand, were found in both experimental groups of females. In the stressed group these correlations were higher.     

Photosynthetic response of Chlamydomonas reinhardtii to short-term storage on ice in darkness. Dependence of the response on growth conditions

The effect of storage of the unicellular green alga Chlamydomonas reinhardtii (strain 137+) in the pelleted state in darkness on ice (0.2–0.5°C) (further simply “SPDI-treatment”) on its photosynthetic and respiratory activities was studied. To this end, the steady-state rates of O₂ exchange in darkness (dark respiration) and under saturating light (apparent photosynthesis) as well as the induction periods (IP) of apparent photosynthesis were measured at 25°C in the SPDI-untreated and SPDI-treated for the period from ～0.5 to ～30 h algal cells. In contrast to expectations, the SPDI-treatment consistently affected the rate and IP of photosynthesis depending on the physiological state of C. reinhardtii. Dark respiration was affected by the SPDI-treatment as well. However, in absolute values the respiratory changes were much less than the photosynthetic ones, and they were insufficiently reproducible. The SPDI-treatment affected photosynthesis most significantly in high-CO₂-grown cells (cells grown at 5% CO₂ in white light). The rate of photosynthesis in these cells declined quasi-exponentially as a function of time during the SPDI-treatment with a t _1/2 ～1.5 h and finally became by about 60% lower than that before the SPDI-treatment. This decline of photosynthesis was accompanied by continuous and essential increase in the photosynthetic IP. The SPDI-induced photosynthetic changes in high-CO₂-grown cells resulted from the firm disfunction of the photosynthetic apparatus. After switch from growth at 5% CO₂ in white light to growth at ～0.03% CO₂ (air) in white, blue, or red light, the alga gradually transited to a physiological state, in which the negative effects of the SPDI-treatment on the rate and IP of photosynthesis became weak and absent, respectively. Remarkably, this transition was faster in blue (≤5 h) than in white and red light (>10 h). Similar changes in the response of the alga to the SPDI-treatment occurred when high-CO₂-grown cells (5% CO₂, white light, 26°C) were incubated in darkness (air, 24–26°C) for 20–25 h. The results of study were analyzed in the light of literature data relating to the effects of CO₂ concentration, darkness, and light quality on carbohydrates in plant organisms. The analysis led to suggestion that there is connection between the negative effect of the SPDI-treatment on C. reinhardtii and nonstructural carbohydrates presented in the alga: the more carbohydrates contain the alga, the more extensive inactivation of the photosynthetic apparatus occurs in it during its storage in the dense (pelleted) state in darkness on ice.     

Possibility of the intrauterine sensitization to benzylpenicillin and ampicillin in Syrian hamsters]

Immunization of Syrian female hamsters with benzylpenicillin and ampicillin resulted in positive skin reactions of the retarded type and decreased titers of the blood antihistamine factor (AHF) in a part of the posterity. Penicillin allergy was in particular observed in the posterity of the female hamsters immunited before the pregnancy. The state of allergy to penicillins was found in the posterity of the female hamsters with both the positive and negative skin reactions on immunization during the 2nd half of the pregnancy.     

Study of blood and lymph in experimental myocardial ischemia and arterial hypertension]

The peripheral blood and central lymph of rats under experimental myocardial infarction was studied by means of light microscopy and electric conductivity measurement. Both hypertensive rats and animals 3 days after myocardial infarction had similar quantity of neutrophils in peripheral blood. Lymph cells count of hypertensive rats by middle lymphocytes is similar to the animals 1 day after myocardial infarction. The correlation between lymph and blood electric conductivity and its cell composition was noted.     

Ultrastructural organization of the endotheliocytes of iliac lymph node capillaries in pregnancy (morphometric study)

Using light and electron microscopy and morphometry, the morphological changes in the lymph nodes of arterial and venous parts of capillaries were studied on the 11th, 17th and 21st days of pregnancy in rats. Ultrastructural changes in endothelial cells of blood vessels in the uterine lymph nodes during normal pregnancy are of adaptive nature and are possibly responsible for the relief of the blood congestion in the system of the inferior vena cava and for the improvement of the utero-placental circulation.     

Effect of selection for behavior on the seasonal characteristics of the reproductive function in brown rats

Artificial selection of grey rats by the domestic type of behaviour resulted in the decrease of the dependence of reproductive function on the effect of photoperiod. Domesticated animals exhibited a significantly lower decrease of the intensity of reproduction in autumn and winter as compared to aggressive ones. One of the causes of this difference is probably the observed shift in the seasonal changes in the level of sex steroids in the blood.