Nebesnyi O. R., Ivanchuk I. M., Hrymalyuk O. I., Tupol L. D., Nebesna Z. M.

ULTRASTRUCTURAL CHANGES OF HEMOCAPILLARIES IN THE CEREBRAL CORTEX OF WHITE RATS UNDER EXPERIMENTAL ONCOGENESIS

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Nebesnyi O. R., Ivanchuk I. M., Hrymalyuk O. I., Tupol L. D., Nebesna Z. M.

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MORPHOLOGY

Type of article:

Scientific article

Annotation:

Cancer pathology remains an important biomedical problem due to the continuously increasing incidence rate and the significant impact of the neoplastic process on various organs and systems of the body. Tumor development is known to be accompanied by pronounced metabolic, vascular, and neurodegenerative disturbances affecting the state of the central nervous system. At the same time, morphofunctional changes in the cerebral cortex under experimental oncogenesis remain insufficiently studied, which determines the relevance and scientific significance of this research. The aim of the study was to investigate ultrastructural changes in hemocapillaries of the somatosensory area of the cerebral cortex in white rats under conditions of DMH-induced carcinogenesis. The study was performed on 30 mature outbred male white rats. Experimental animals were divided into control and experimental groups, in which a model of colorectal adenocarcinoma in situ was induced using N,Ndimethylhydrazine hydrochloride. Small fragments of the cerebral cortex were collected for electron microscopic examination. Tissue processing and preparation were carried out according to standard conventional methods. Ultrathin sections were examined using a PEM-125K electron microscope. Electron microscopic examination of hemocapillaries in the cerebral cortex of animals with experimentally induced colorectal carcinogenesis in situ revealed significant ultrastructural alterations. The detected changes were manifested by destruction of the hemocapillary wall, uneven thickening of the basement membrane, chromatin condensation in endothelial cell nuclei, and damage to cytoplasmic organelles. Areas of cytoplasmic clearing and edema, damage to the luminal cell surface, and partial loss of intercellular junction integrity were observed. Pronounced perivascular edema was also detected. Damage in the ultrastructure of pericytes has been determined. A significant decrease in the number of micropinocytotic vesicles was identified, indicating impaired transendothelial transport and deterioration of trophic processes in nervous tissue.

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Publication of the article:

«Bulletin of problems biology and medicine», 2026 Issue 2, 181, 253-257 pages, index UDC 616-006:611.811.018.54-076.4:611.843:599.323.4

DOI:

10.29254/2077-4214-2026-2-181-253-257