Ukrainian Journal of Veterinary Sciences

Morphological features of the kidneys in 2-4-month-old Wistar rats

Viktoriia Lisova, Roman Bokotko, Tomasz Gębarowski, Roman Dymko, Maksym Zhukovskyi
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Abstract

The relevance of the proposed study is related to the wide distribution of Wistar rats in veterinary and biomedical research, while the anatomy and microanatomy of their kidneys at 2-4 months of age are not sufficiently investigated. This study aimed to determine the characteristics of the anatomical and microscopic structure of the kidneys in Wistar rats of the specified age. Anatomical dissection, macroscopic examination of the kidneys and histological analysis of their structural elements were performed for the implementation of the aim of the study. The kidneys of both male and female Wistar rats of 2, 3, and 4 months of age exhibited the typical structure of the organ, including its dark red colour, bean-shaped form, fibrous connective tissue capsule, and division into cortical and medullary regions. It has been established that the cortical and medullary areas of the kidney have characteristic structural features (such as medullary rays, kidney pyramids, and kidney columns). Within the kidneys, the number of mesangial cells within the renal corpuscles was variable, as were the diameters of the glomerular capillaries; those corpuscles that contained fewer mesangial cells had more dilated capillaries and more blood within their corpuscles. In the proximal convoluted tubules, the nuclei of epithelial cells were often shifted to the luminal surface; the lumen of these tubules often contained proteinaceous masses. The distal convoluted tubules had a more elongated shape, the nuclei of the epithelial cells were often located in the centre of the cells, and the proteinaceous masses accumulated in the lumen did not cause narrowing of the distal tubule lumen. All the collecting duct system tubules consisted of simple cuboid epithelium cells; their cytoplasm was light, and the nuclei were predominantly central. The results obtained can be used in practical experiments in the morphological studies and applied in such disciplines as comparative anatomy, histology, embryology, and veterinary medicine

Keywords

renal corpuscles; mesangiocytes; proximal convoluted tubules; distal convoluted tubules; collecting ducts; cortex; medulla

Suggested citation
Lisova, V., Bokotko, R., Gębarowski, T., Dymko, R., & Zhukovskyi, M. (2026). Morphological features of the kidneys in 2-4-month-old Wistar rats. Ukrainian Journal of Veterinary Sciences, 17(2), 57-74. https://doi.org/10.31548/veterinary2.2026.57
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