Vol 159, No 2 (2021)

Recently, a lot of data has been gathered which demonstrates neurogenesis in the brain of adult humans. In genetics, findings have been obtained that not only prove, but also elucidate the molecular mechanisms of neurogenesis. In some publications, however, morphology disputes neuronal renewal in adulthood. Therefore, this review presents the modern achievements of epigenetics, morphology, and physiology, which confirm and characterize postnatal neurogenesis in detail. We suggest that the introduction of molecular genetic technologies into morphological studies will be the starting point for the integration of these areas, complementing each other for the introduction of targeted therapy in clinical practice. Numerous evidence has been obtained of the presence of postnatal neurogenesis in adult humans in studies using bromodeoxyuridine, a carbon isotope of ¹⁴C, and ³H-thymidine, in comparative analyses of experimental data from animals. Neuronal stem cells, represented by radial glia present in the subventricular and subgranular zones of the human brain, are morphologically similar to neuroepithelial cells. They express marker proteins for astrocytes, which suggests that the proliferation of neuroglia found in adults can also indicate the regeneration of neurons. To prove this, further studies are required, with the exact identification of newly-formed cells, using specific molecular markers, and data from modern epigenetics. The integration of molecular genetic methods into morphology will facilitate not only the accurate determination of the classification of cells to a specific subpopulation but also to study the effects of various agents on the proliferation of neurons in the adult brain.

AIM: The work aimed to analyze the morphological and functional state of seminiferous epithelium in the offspring of female rats with experimental diabetes mellitus (DM).

MATERIALS AND METHODS: Studies were conducted on white Wistar laboratory rats (females) with diabetes mellitus induced and their 70-day-old offspring. Diabetes mellitus was reproduced according to the generally accepted method using streptozotocin. The areas of parenchyma and stroma, the number and area of convoluted seminiferous tubules, the total count of spermatogenous cells and their subpopulation composition, and the count of Sertoli cells per one convoluted seminiferous tubule were determined on serial histological specimens of the testes of offspring of the DM mothers. A number of generally accepted indices were determined, including the spermatogenesis index, spermatogenesis relaxation index, and germinative index.

RESULTS: The offspring of female rats with experimental DM has been established to have a decreased area of the testicular parenchyma and an increase of the area of its stroma, as well as a reduced total count of spermatogenic cells, including primitive sperm cells, primary and secondary spermatocytes, spermatids and, as a result, a decrease in the count of spermatozoa. The results are consistent with a decrease in the spermatogenesis index in the offspring of female rats with experimental DM. A study of the count of Sertoli cells in experimental animals did not reveal significant differences, however, an analysis of the germinative index and the spermatogenesis relaxation index revealed a significant decrease in these parameters in experimental animals compared to the control.

CONCLUSIONS: Offspring with reduced generative function of the testes is born in female rats with experimental type 1 DM.

AIM: To compare morphological changes that occur in renal tissue, as a result of exposure to various models of light desynchronosis.

MATERIAL AND METHODS: This study was conducted on 48 white rats. Three experimental groups were exposed to light for 21 days. The LL (0:24) model was studied in the first group, while the LD 18:6 and 12:10 models were studied in the second and third groups, respectively. The control group was kept in natural conditions all through the experiment.

The animals were placed under anesthesia with a combination of Telazol (ZoetisInc, USA) and Xylanit (Nita-farm, Russia). Afterward, their right kidney was removed. The samples obtained were prepared according to the standard method. Statistical processing was performed using the package of applied statistical programs "STATISTICA 10" (StatSoft ®, USA).

RESULTS: Morphological disorders of the renal tissue were observed in the three experimental groups. In the first experimental group, there was a significant segmentation of the glomeruli, accompanied by dystrophic changes in the renal tubules. In the second experimental group, glomerular segmentation was more pronounced. In the renal tissue of animals of the third experimental group, the disorders were highly observable, and the sclerotized segment is noted. Changes in morphometric indicators were significant across all experimental groups.

CONCLUSION: Desynchronosis harms the renal tissue by causing changes in its morphology. The most significant disorders characterized by sclerosis were observed in the kidneys of animals in the third experimental group.