Vol 152, No 4 (2017)

In the experiments on Wistar rats (n=18), the dynamics of ionotropic glutamate receptor GluR2 subunit expression was studied in respiratory subnuclei (ventral and lateral) of the solitary tract nucleus (STN). The observations were performed in the early postnatal period (days 5, 10 and 20; 5-6 animals in each group) in norm and after prenatal serotonin depletion, which was achieved by inhibition a tryptophan hydroxylase by para-chlorophenylalanine. Immunocytochemical demonstration of GluR2 has shown that its expression was approximately equal in both respiratory subnuclei during the early postnatal period. By the juvenile age, there was a significant increase of GluR2 expression (2-fold in lateral subnuclei and 2,6-fold in ventral subnuclei). Prenatal serotonin deficiency changed the expression of GluR2 in respiratory subnuclei of STN. In the early postnatal period, the significant delay of GluR2 expression, that raised to control values by the second postnatal week, however by juvenile age the expression of GluR2 was twice lower than in the control. Disturbances of glutamatergic receptor network in the respiratory subnuclei can be the basis for the respiratory dysfunctions.

Superficial peroneal nerve was studied in adult (1-3 years old) clinically normal mongrel dogs (n=5) using the methods of scanning electron microscopy and morphometry on total semi-thin (1 μm) araldite sections. Nerve trunks were found to be formed by many bundles; they had scant blood supply by 1-2 epineural magistral small-caliber arteries. The numerical density of arterioles, venules and capillaries in the endoneural microcirculatory bed endoneurium was equal to 141.8±8.7 in 1 mm2. Major part of these vessels (71%) had open lumina, while in 29% it was slit-shaped. The mean diameter of myelin fibers was 6.46±0.07 μm, that of their axons - 4.50±0.08 μm, the thickness of the myelin layer was 1.04±0.04 μm. Medium and large caliber myelinated fibers prevailed (77%), resulting in high values of Shannon entropy (3.243 bits).

Variant anatomy and topography of myocardial bridges and loops were examined by macro-microscopic preparation and histotopographic method in hearts obtained from cadavers of 55patients who died from diseases unrelated to cardiac pathology. The frequency of detection of myocardial bridges and loops was 65.4%. One to five myocardial bridges and loops could be found in one heart. The ranges of variations of their width and topography were determined. Differences in the frequency of location of myocardial bridges and loops around left and right coronary arteries and their main branches were demonstrated. It is suggested that myocardial bridges and loops are an integral part of coronary artery topography, specifically, of major branches of left coronary artery: anterior interventricular and circumflex arteries.

The effect of exposure to chronic heterotypic stress on the spleen was studied in Sprague-Dawley rats (n=48) of different age groups (infantile and peripuberal periods of ontogenesis) using immunohistochemical methods. Immunohistochemical reactions were performed on histological sections of the spleen using the antibodies against markers of lymphoid and dendritic cells, proliferation and apoptosis, with subsequent image analysis. The study demonstrated that in the infantile heterotypically stressed animals the morphometric parameters of populations of both T-(CD4+, CD8+, CD90+) and B-cells (CD20+) in the spleen were reduced more than in the peripuberal rats. In both age groups this reduction was more significant in heterotypic stress group compared to the homotypic stress-exposed animals. The number of the OX-62+ dendritic cells decreased only in the peripubertal rats exposed to stress, with insignificant differences between homo- and heterotypic stress groups, while the number of the follicular dendritic cells was reduced in both ages with significant differences between homo- and heterotypically stressed groups. Thus, heterotypic stress-induced immunomorphological changes in the spleen have different age-related pattern compared to those induced by the homotypic stress. This may be associated with diverse hypothalamo-hypophyseo-adrenal axis activation patterns in immature animals of various age groups exposed to different types of stress.

Ultrastructural characteristics of the foot processes fusion and glomerular basement membrane (GBM) denudation were studied as a manifestation of podocyte (PC) dysfunction. The following variants of podocytopathies were analyzed: focal segmental glomerulosclerosis (n=8), membranous nephropathy (n=17), minimal change disease (n=12). Renal biopsy material was examined by light and electron microscopy with the determination of some morphometric indices. Morphological data were compared with the results of standard laboratory tests of renal function. In various podocytopathies significant changes in the ultrastructure of PC were observed that caused the disorders of the selective permeability the glomerular filter. These dysfunctional changes were characterized by foot process fusion and GBM denudation. Negative correlation was found between the glomerulosclerosis severity and glomerular filtration rate - the main indicator of the preservation of renal function. Correlation analysis of the width of foot processes and the extent of GBM denudation demonstrated a statistically significant negative relationship. The changes detected in PC seem to be an adaptive response of the cells, opposing the desquamation from the GBM surface under conditions of stress and action of damaging factors.

Histological, histochemical, immunohistochemical and morphometric methods were used to study 12 samples of placenta with the mass of 650-800 g, obtained from monozygotic twins with common chorion, and 12 samples of placenta with the mass of 450-550 g from singleton pregnancies. Gestational age was 39-40 weeks, the course of pregnancy was without pathology and resulted in uncomplicated delivery. In the epithelium of the terminal villi in the placenta of the monozygotic twins, the number of Ki-67-immunopositive nuclei was 3 times higher than in placentas in singleton pregnancies. The number of Ki-67-immunopositive nuclei in the endothelium and in smooth muscle cells of the blood vessels in the villi in twin pregnancy was higher that in singleton pregnancy. These data indicate that the mechanisms of angiogenesis is involved in the vascularization of the villi. The results obtained in this study suggest that the villous tree in the monochorionic placenta in the development of twins in humans was characterized by incomplete histogenesis of the main structural components of the terminal villi.

Morphological changes of spermatogenic epithelium were studied in 162 infertile men aged 18 to 46 years. Testis biopsy was performed in patients before the ICSI (Intra Cytoplasmic Sperm Injection) cycle. Seminiferous epithelium was examined on serial histological sections of the testicular biopsy specimens. The results of the study have demonstrated spermatogenic epithelium hypoplasia and subtotal aplasia, Sertoli-cell-only syndrome, and atrophy of convoluted seminiferous tubules. In patients with pathospermia, a decrease in the content of spermatogonia, spermatocytes and sustentocytes (Sertoli cells) was recorded. The number of sustentocytes may be used as a predictor of spermatogenesis preservation.