INTRODUCTION: The aging kidney is characterized by numerous morphological changes in the nephrons and interstitium which are usually associated with failure of renal function. The aim of the present study is to describe and compare histological age-related changes in the kidney in three age groups of rats.
MATERIALS AND METHODS: Male Wistar rats aged 2, 4 and 6 months (n=3; per age group) were used in the present study. Alterations in kidney morphology were observed by light microscopic analysis using PAS reaction and Mallory`s trichrome staining.
RESULTS: We observed normal histological structure of the kidney in 2-month-old rats. We noted that renal corpuscles were relatively well preserved and proximal and distal tubules were visible as well-defined structures. No pathological changes in blood vessels and interstitial fibrosis were observed. As age advanced (4 and 6 months) we described periglomerular and periarteriolar sclerosis, wrinkling and thickening of glomerular and tubular basement membranes; interstitial fibrosis was generally expressed.
CONCLUSION: Renal aging is a multifactorial process characterized by an increased number of sclerotic glomeruli, tubular atrophy and interstitial fibrosis and is associated with declining renal function.
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