The present study is an investigation of the histological and ultrastructural effect of aging on the kidney of male albino mice, and the possible modulatory role of vitamin E, vitamin C or zinc sulfate. The aged animals were daily administered a therapeutic dose of vitamin E (1.56 mg kg b. wt), vitamin C (1.9 mg kg b. wt) or zinc sulfate (0.12 mg kg b. wt) then tissue were examined histologically and ultrastructurally after one month. Aged kidney showed variable changes like obliterated filtration space, lobulated capillaries and necrotic tubules, while after antioxidant treatment with vitamin E, vitamin C, or zinc a noticeable progression had occurred and represented in apparent preserved glomeruli with clear filtration space and approximately normal PCTs and DCTs. In contrast, after treatment of the adult normal mice with one of these different substances little harmful effects were seen, e.g. enlargement of the glomeruli and narrowing of the filtration spaces after zinc treatment. Also obliterated filtration spaces and some few necrotic tubules were seen with vitamin E treatment. While after vitamin C treatment there was no histological effects were seen. A decrease of the carbohydrate content of kidney tubules was observed in aged animals which were improved after antioxidants treatment. Ultrastructural examination of kidney of aged mice revealed several changes in cell organelles of the kidney; these appeared clearly in damaged mitochondrial cristae, shrunken nuclei with irregular nuclear membrane, fragmented rough endoplasmic reticulum, large number of vacuoles, fat droplets and damaged microvilli of the kidney proximal convoluted tubules. After treatment with zinc sulfate, a great improvement was seen represented in approximately preserved mitochondria, well organized rough endoplasmic reticulum, apparently normal centrally located nuclei, very small number of fat droplets, more or less normal glycogen granules in the cytoplasm, also approximately preserved microvilli in the proximal convoluted tubules.
Key words: Aging, antioxidants, kidney tissue, ultrastructure, histochemical investigations
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