INTERSTRAIN DIFFERENCES IN EMOTIONAL AND WEIGHT INDICES IN GC RATS WITH CATATONIC RESPONSE AND WISTAR RATS

In selecting rats for behavior, we observe a direct natural effect and affect the nonspecific stress function. In this process, new behavioral phenotypes appear in the strain under selection. They differ from the selected forms in the selection criterion. In the GC strain, a large proportion of the so-called nervous rats emerge. The criterion presumes the selection for the long cataleptic freezing character, whereas the nervous rats display elevated motor excitement: running, jumping, and vocalization. The main purpose of our study was to assess phenotypic indices in GC rats (abbreviated from genetic and catatonia) and recognize principal components of variability for emotional and weight indices. Rats of the ancestral Wistar population were taken as control. The following indices were measured: time of cataleptic freezing, excitement level, blood pressure, acoustic startle response, seizure  activity, and weights of the heart, kidneys, adrenals, and spleen. Multivariate analysis methods were applied: factor analysis and principal component analysis. We confirmed the inclination of GC rats of the generation studied to freezing in quiet surrounding and after a strong acoustic sti - mulus. More pronounced startle responses,  moderate hypertension, and larger weights of the heart and adrenals were noted. Two principal variability components were recognized: startle amplitude (PC1) and morphofunctional variability (PC2). The figure shows different locations of Wistar and GC individuals in principal component coordinates. The principal component method confirmed the genetic relationship between the startle and nervousness responses. It was shown that in PC2 the indices of heart, kidney, adrenal, and spleen weight exert negative effects, whereas the effects of startle and nervousness were positive. In the same component, an increase in the startle and nervousness responses positively correlates with the relative weights of the heart and adrenals. Differences in the directions of the contributions to the second component of morphofunctional variability are discussed

SPERM QUALITY IN RATS PREDISPOSED TO THE MANIFESTATION OF CATATONIC REACTIONS

Catatonia is a psychopathological syndrome displayed as a motor disorder. Catatonia is a sign of many menthal disorders, particularly schizophrenia and depression, with a wide disrtibution in the human population. The GC (“genetic” and “catatonia”) rat strain was obtained from the Wistar rat strain by a long selection (78 generations) for the catatonic type of reaction and is a model of schizophrenic and depressive disorders in humans. It is known that selection for behavior including catatonic reactions results in neuroendocrine, reproductive and morphological changes in animals. However, the influence of selection for a catatonic reaction on the spermatogenic function of testes had not been studied. The aim of this study was to conduct a comparative investigation of sperm quality in rats of the GC and the Wistar strain. The epididymal sperm parameters (sperm count, sperm motility, sperm morphology) were measured, and body, testes and epididymal weight were determined at puberty (50 day of life) and at adulthood (90 day of life). The litter size of the GC and Wistar rats was determined. It was found that adult GC rats had a lower sperm count, sperm motility, testis weight, epydidymal weight and litter size compared to adult Wistar rats. However, at puberty, GC rats had a higher sperm count than the Wistar strain. Interstrain differences in sperm morphology were not found. It has been assumed that the changes of spermatogenic parameters in response to selection for catatonia are caused by changing the ontogenic pattern of testosterone secretion. In conclusion, the hereditary predisposition to catatonic reaction is associated with impaired sperm parameters in adult rats that reduces their chance to reproduction. The GC rat strain can be a perspective model for investigation of the relationship between the hereditary predisposition to catatonia and spermatogenesi

Destabilization signs in behavioral and somatovegetative parameters of rats selected for catatonia

The article presents data on destabilization signs in response to selection for catatonia at an organismal level. Experiments were conducted with the unique GC (genetic catatonia) rat strain selected for long passive-defensive freezing. The goal of this study was to detect destabilization signs in the behavioral and somatovegetative parameters of GC rats emerging in response to selection. The destabilization manifested itself as changes in rat attitudes towards humans, as became apparent from the glove test. Altered hormone levels in GC rats were detected: corticosterone concentrations were reduced in feces and increased during handling. The metabolic system showed a decrease in energy stored accompanying the fast (glucose level) and slow (triglyceride level) responses. However, the strains did not differ in the concentration of insulin, which affects glucose transport through the cell membrane. Nor did we find differences between Wistar and GC rats in cholesterol level. This lipid is important for both energy and constructive metabolism. A side effect of selection for catatonia was the worse pelage status in GC rats. The overall physical condition of catatonic rats involved reduced body weight in both neonates and adults. All these changes point to the modification of behavioral and somatovegetative patterns and intensification of the passive-defensive component of selection in GC rats

Expression of catecholaminergic genes in the midbrain and prepulse inhibition in rats with a genetic catatonia

The GC rat strain (from the words "genetic" and "catatonia") was created by selection for predisposition to passive-defensive reaction of catatonic freezing in response to stressing stimuli. Rats of the GC strain have previously demonstrated a number of biochemical and behavioral properties similar to those of patients with schizophrenia and depression. Prepulse inhibition (PPI) is widely explored as an important indicator, a decrease of which may be indicative of psychopathology, including schizophrenia. It has been established that the brain noradrenergic system influences the manifestation of PPI, in particular through the activation of central alpha-adrenoreceptors. Also known is the association between PPI and expression of catechol-O-methyltransferase. This study focuses on the reaction of prepulse inhibition in rats of the inbred GC strain, being considered as a hypothetical model of schizophrenia, as well as on the relation of prepulse inhibition to mRNA expression of tyrosine hydroxylase, catechol-O-methyltransferase, alpha1A- and alpha2Aadrenergic receptors in the midbrain of GC rats. For the first time, a decrease of PPI in GC rats compared with WAG rats was shown, both with a prepulse power of 75 dB and at 85 dB, which may indicate a violation of filtration of sensorimotor information into the central nervous system in GC rats. Real-time PCR showed a decrease in mRNA level of Adra1A in intact rats with genetic catatonia when compared to control WAG rats. There was observed no correlation between the expression of mRNA of the Adra1A, Adra2A, Th, and Comt genes in the midbrain and the PPI reaction in GC rats. The reduction of prepulse inhibition in GC rats indicates functional similarity of this genetic model of schizophrenic psychopathology with a prototype. © AUTHORS, 2017.Russian Foundation for Basic Research, RFBR: 16­04­013250324­2016­0002This study was supported by the Russian Foundation for Basic Research, project 16­04­01325, and State Budgeted Project 0324­2016­0002

Changes in the crystal lattice parameters of montmorillonite during its modification by cobalt and aluminum cations

The effect the modification (pillarization) of montmorillonite clays from different locations has on the crystallographic lattice parameters of montmorillonite is determined. It is revealed through ultrahigh resolution transmission electron microscopy and analyzing microdiffraction patterns that pillarization raises the distance between montmorillonite structural units to 2.2 nm, while the intracrystal distance between the atoms grows by 0.4 n

Results of Epizootiological Monitoring of Natural Foci for Bacterial Vector-Borne Infections in Caucasian Mineral Waters Region of the Stavropol Territory in 2018–2020

The aim of the study was to assess the epizootiological situation on bacterial vector-borne infections in Caucasian Mineral Waters area of the Stavropol Territory over the period of 2018–2020.Materials and methods. 3494 specimens of ticks (473 pools), 257 specimens of small mammals, 9 regurgitates of birds of prey and mammals, 7 excreta samples of small mammals, and 2 water samples were tested. Laboratory research of the field material was carried out using molecular-genetic, serological, biological methods. Statistical analysis of laboratory results was conducted using Microsoft Excel 2010. The data were mapped using QGIS 2.18 software.Results and discussion. The study revealed that the 44.8 % of collected ticks were positive for tick-borne borreliosis, 21.5 % – for tick-borne rickettsiosis, 10.3% – for human granulocytic anaplasmosis, 2.7 % – for Q fever, 0.84 % – for tularemia. There has been an increase in the percentage of positives for tick-borne borreliosis agent samples (more than three times) and a decrease in this indicator for human granulocytic anaplasmosis (1.5 times) as compared with 2010–2012. Investigation of tick infection with the agents of Q fever and tick-borne rickettsioses has not been previously conducted in the region. During the period under review, 19 pools of ticks had mixed infection, which indicates that there are combined foci of bacterial natural-focal infections with vector-borne transmission in the recreation zone of the Stavropol Territory. This necessitates preventive measures and systematical epizootiological surveys in the Caucasian Mineral Waters region