5/6 nephrectomy: renal tissue regeneration and condition of brain microcirculation

Abstract

THE AIM. To find out if the level of regeneration of renal tissue after nephrectomy 5/6 kidney mass is sufficient to prevent pathological deterioration of microcirculation in the cerebral cortex. MATERIAL AND METHODS. The method of intravital microscopy was used to study the density of the microvascular network of the pial sheath of the cerebral cortex in Wistar rats 4 months after the removal of 5/6 of the renal tissue mass. At the same time, the level of perfusion and oxygen saturation (SO2) were measured in the cortical tissue using laser Doppler flowmetry. To assess the degree of kidney regeneration after resection, a morphological study of kidney tissue was carried out when staining with hematoxylin-eosin and Masson. RESULTS. It was shown that 4 months after nephrectomy in the pial membrane, the density of the microvascular network decreased by an average of 1.3 times compared with falsely operated animals, and the number of arterial vessels by 1.5 times. The level of tissue perfusion (on average by 20%) and SO2 (on average from 95 to 91%) decreased statistically significantly. On morphological preparations, there were no signs of true regeneration; revealed glomerular hypertrophy, the development of fibrosis, deformation of blood vessels, and tubular structures. CONCLUSION. Renal regeneration 4 months after nephrectomy 5/6 kidney mass is insufficient to normalize its function, and therefore does not prevent the cerebrovascular accident. Significant microcirculation disorders are observed in rat cerebral cortex: a decrease in the density of the microvascular network, a decrease in the rate of cerebral blood flow and tissue oxygen saturation, which are signs of the formation of lacunar strokes.