Гидропическая дистрофия сенсомоторной коры белых крыс в контексте формирования темных нейронов и изменения нейроглиальных взаимоотношений после краткосрочной окклюзии общих сонных артерий

Abstract

Introduction. Neurodegenerative processes are key in the development of a number of diseases — strokes, Parkinson’s and Alzheimer’s diseases, epilepsy, and traumatic brain injury. They include primary and secondary structural and functional changes in the nervous tissue, as well as the death of neurons and complete loss of functions. Aim. To study the manifestations of hydropic degeneration and reorganization of glio-cytoarchitectonics during the formation of dark neurons in the sensorimotor cortex (SMC) of the cerebrum of mature white rats in 40 min after the common carotid arteries occlusion (CCAO). Materials and methods. A 40-minute CCAO was simulated in white Wistar rats. The brain was fi xed by perfusion method. Morphometric assessment of manifestations of edema — swelling, cyto- and glio-cyto-architectonics of SMC was performed normally (n = 6, control group), on the 1st (n = 6), 3rd (n = 6) and 7th days (n = 6) after CCAO. The Nissl staining, hematoxylin and eosin, immunohistochemical typing NSE, MAP-2, GFAP and AIF1 were applied. The relative area of edema-swelling zones, the numerical density of normochromic and dark pyramidal neurons, oligodendrocytes (OD), microgliocytes (MG) were determined. Results. The high content (20–50%) of dark neurons after CCAO was accompanied by a 3.3-fold increase in the relative area of edema-swelling zones (r = 0.82, p = 0.01). Specifi c proteins (NSE, MAP-2) of most dark neurons were preserved. The total numerical density of SMC neurons decreased by 26.4% (layer III, p = 0.001) and 18.5% (layer V, p = 0.01) after 7 days of CCAO. The content of astrocytes, MG and OD increased. The peak in the number density of MG was observed in the 1st day, and OD — in the 7th day after acute subtotal ischemia (p ≤ 0.001). The revealed changes were of a diffuse-focal nature. Conclusion. After a 40-minute CCAO, the content of dark neurons in SMC increased and, as a result, signs of hydropic degeneration appeared. Against this background, the number of satellite OD, astrocytes and MG increased. Probably, edema-swelling, active MG and astrocytes previously (on the 1st – 3rd day) sanitate the nerve tissue, ensuring its subsequent (on the 7th day) structural and functional recovery with the participation of OD