Age-related histological changes in kidneys of Brown Norway rat.

In this study, age-dependent histological changes in the kidneys of Brown Norway rat, a strain useful for conducting aging research, were evaluated. Examination was performed at 3, 12, 18, 24 and 30 months of age. Sclerotic and hypertrophic changes of the glomeruli were observed, and quantitative scores of these changes persistently increased with age. A marginal increase in scores was observed for glomerular cystic changes and tubulointerstitial damage. Further, urothelial hyperplasia was observed in the renal papillae, particularly at 30 months of age. In conclusion, the findings of the present study demonstrate that the Brown Norway strain exhibits persistent, but mild progression of age-dependent renal histological changes.