Spontaneous Age-Related Pathology Of The Urinary System In Rats

K. Zaikin(1), E. Gayday(2), D. Gayday(2), Ya. Gushchin(1), A. Muzhikyan(1), K. Kryshen(2), M. Makarova(1) 1-Scientific-Production Organization «Houm оf Pharmacy» 188663, Leningradskiy region, Vsevolozhskiy district, Kuzmolovskiy, 3, Zavodskaya st., b. 245, Russia; 2-1Institute of pre-clinical studies 188663, Leningradskiy region, Vsevolozhskiy district, Kuzmolovskiy, 3, Zavodskaya st., b. 245, Russia Е-mail: gajdaj.ea@doclinika.ru


Summary. The article is devoted to spontaneous age-related pathologies of the urinary system of rats detected in animals of control group in a long-term carcinogenesis experiment. Interest in this group of pathologies is relevant during long-term experiments since the elderly rodents’ death is often associated with oncological diseases and pathologies of the kidneys. Knowing of pathologies with spontaneous manifestation in laboratory rats is necessary for correct interpretation of experimental results as well as for the differential diagnosis of «spontaneous» and «induced» pathologies. For the classification of pathologies INHAND nomenclature was used. Histological examination of the organs of urinary system (kidney and bladder) was carried out in 200 males and 200 female Wistar rats aged 24 months. Tumor pathology in the article is not considered. Spontaneous age-related pathology of the urinary system in rats is very common - kidney pathology was found in all 200 males studied and in 165 of 200 females studied. Pathological changes considered as manifestations of chronic progressive nephropathy (such as interstitial inflammatory cell infiltration, glomerulosclerosis, basophilia and atrophy of renal tubule epithelium, tubular dilatation, cylinders in the lumen of tubules, focal interstitial sclerosis of the renal cortex) are most common; all 200 males studied and 140 of 200 females studied were identified. Vesicular dystrophy (vacuolization) of renal tubules epithelium is only pathology of urinary system that is more common in females than in males. Vesicular dystrophy has a diverse pathogenesis its clinical and biological significance is ambiguous it can precede necrosis of epithelium, but it can also occur in normal conditions. Pathology of bladder is less common it was detected in 22 males and 1 female. Among the pathological changes were protein plugs in the lumen of bladder and focal inflammatory cell infiltration of bladder. In the experiments described pathologies should be considered as spontaneous associated with age-related changes in the body.


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