Pleiotropic effect of the hooded mutation of the rat on male fertility

Several reproductive parameters were studied in males homozygous (hh) or heterozygous (Hh) for the hooded mutation as compared with completely pigmented wild-type males (HH). Histological analysis of the testes was carried out in males of the three genotypes. The proportion of sterile males in homogeneous matings of homozygotes hh was twice as high as in matings of heterozygotes. The proportion of sterile males in matings yielding no progeny was also twice higher in homozygotes hh as compared with heterozygotes. No sterile males were detected in matings of completely pigmented wild-type animals. Unilateral cryptorchidism, a hypoplastic testis combined with a hyperplastic one, or hypoplasia of both testes were observed in some males homozygous for the hooded mutation. Morphologically, these defects were associated with underdevelopment or the complete absence of spermatogenic epithelium or with the presence of gaps and cells with large nondivided nuclei in the epithelium. The results showed that the hooded coat-color mutation exerts a pleiotropic effect on male fertility in rat.     

Participation of 5-HT1A-receptors in regulating various types of aggressive behavior

We studied the effects of selective agonists of 5-HT1A receptors 8-OH-DPAT and flesinoxan on aggressive behavior of C57BL/6 male mice in the "resident-intruder" test and on defensive aggression of Norway rats toward man. 8-OH-DPAT (0.4 mg/kg, i.p.) significantly reduced the intermale aggression in mice and defensive aggression in rats (0.1-0.5 mg/kg, i.p.). In the dose of 0.5 mg/kg, flesinoxan inhibited the aggressive behavior in mice. These results suggest that activation of 5-HT1A receptors reduces different kinds of affective aggression. The results are discussed in terms of interaction between the well-known anxiolytic effects of 5-HT1A agonists and their antiaggressive properties.     

Effect of stress and immune stimulus on the pituitary-adrenal axis in gray rats selected for behavior

A comparison of effects of the restrain stress, and lipopolysaccharide and interleukin-2 treatment on pituitary-adrenal system of tame and aggressive rats, was examined. It was found that plasma ACTH and corticosterone levels in response to restrain stress and lipopolysaccharide treatment were significantly decreased in the tame rats compared to aggressive ones. By contrast, the maximum corticosterone level was the same in plasma of both groups after interleukin-2 treatment, although the time patterns of the response were different. Thus the selection of wild grey rats for tame behavior results in change of the response of the pituitary-adrenal axis to the immune stimulus. It is conceivable that the interaction between pituitary-adrenal axis and immune system also changes in tame rats.     

The effect of electric field on the spatial-time patterns in the reaction-diffusion system

A model of electrodiffusion processes in the vicinity of cell membrane was developed. The model takes into account chemical reactions, Coulomb interactions between charged particles and the effect of external electric field. It was concluded that the applied electric field can change the characteristics of space-time patterns in the system. Dissipative structures slowly move and this is accompanied by a change in the number of structure elements. The characteristic equation includes odd powers of the wavenumber, which can lead to the appearance of soliton-like structures. The dissipative structures can appear not only due to the Turing diffusion instability but due to the disperse instability under electric field the applied.     

The influence of low doze gamma-irradiation on life span of Drosophila mutants with defects of DNA damage sensation and repair

It was shown that life span of wild type strain Canton-S increased after low doze gamma-irradiation. It was revealed the decrease of life span after irradiation in Drosophila mutants with defects of DNA damage sensation and repair genes mei-9 and mei-41, both in homozygous and heterozygous lines. In mei-41 line males' lives longer than females in contrast to other lines.     

An experiment on fox domestication and debatable issues of evolution of the dog

This paper is a review of the results of the authors obtained in a long-term experiment on fox domestication. Debatable issues of dog evolution are discussed in light of these results. It is demonstrated that genetic physiological mechanisms of the behavior transformation during selection and the nature of the arising phenotypic changes are associated with retarded development of corresponding ontogenetic processes. As a result of this retardation, the adult animals retain juvenile traits of behavior and morphology (the phenomenon of neoteny). The role of hormonal changes caused by domestication in the evolutionary origin of neoteny is discussed.     

Multidrug resistance-associated protein-1 (MRP1) genetic variants,MRP1 protein levels and severity of COPD

Background

Multidrug resistance-associated protein-1 (MRP1) protects against oxidative stress and toxic compounds generated by cigarette smoking, which is the main risk factor for chronic obstructive pulmonary disease (COPD). We have previously shown that single nucleotide polymorphisms (SNPs) in MRP1 significantly associate with level of FEV₁ in two independent population based cohorts. The aim of our study was to assess the associations of MRP1 SNPs with FEV₁ level, MRP1 protein levels and inflammatory markers in bronchial biopsies and sputum of COPD patients.

Methods

Five SNPs (rs212093, rs4148382, rs504348, rs4781699, rs35621) in MRP1 were genotyped in 110 COPD patients. The effects of MRP1 SNPs were analyzed using linear regression models.

Results

One SNP, rs212093 was significantly associated with a higher FEV₁ level and less airway wall inflammation. Another SNP, rs4148382 was significantly associated with a lower FEV₁ level, higher number of inflammatory cells in induced sputum and with a higher MRP1 protein level in bronchial biopsies.

Conclusions

This is the first study linking MRP1 SNPs with lung function and inflammatory markers in COPD patients, suggesting a role of MRP1 SNPs in the severity of COPD in addition to their association with MRP1 protein level in bronchial biopsies.     

The role of glucocorticoids in the appearance of coat depigmentation in animals selected for behavior

The involvement of glucocorticoid hormones in the appearance of white spottings during embryogenesis in domesticated gray rats was studied. It was shown that prenatal stress and exposure to dexamethasone on the 12-14 days of pregnancy of fully pigmented gray rats elicited the slowing of melanoblast migration and its development in embryos. It was associated with a 4-fold increase of the offspring percentage with the depigmentation on the ventral side of body in adults. It was also demonstrated that response of H PA axis to emotional stress was lower in adult offsprings from prenatal-stressed and dexamethason-treated mothers than in adult offspring from control mothers. The role of glucocorticoids in the appearance of coat depigmentation under animal domestication is discussed.     

Modelling of pattern formation and oscillations in pH and transmembrane potential near the cell membrane of Chara corallina

A mathematical model of potencial-dependent proton transfer across the membrane of Chara corallina cells is considered. To construct the model, partial differential equations describing the system dynamics in time and in space were used. The variables of the model are the proton concentration and membrane potential. The model describes the experimentally observed inhomogeneous distribution of transmembrane potential and pH along the membrane and oscillations of the potential and pH in time. A mechanism of the distribution of pH and membrane potential along the Chara corallina cell is suggested.