A Stereological Study of Diabetic Kidney Following Administration of Different Doses of Streptozotocin.

The absolute glomerular volume and total glomerular number as well as renal volume in diabetic rats following administration of different doses of Stereptozotocin (STZ) have been estimated by using unbiased stereological methods. 30 male Wistar rats were randomly divided into 5 groups. Diabetes were induced by IP injection of 15mg/kg, 45mg/kg and 90 mg/kg of STZ. Fifty six days after IP injection, animals were anesthetized by ketamine hydrochloride, the kidneys were excised and fixed in modified Lilli′s solution. After tissue processing and staining, stereological methods used to estimate volume of different zones of kidney, absolute glomerular volume and total glomerular number. This investigation revealed that increment of cortical tissue volume in all groups and increase in medullary volume only in the group 90 mg/kg of STZ (p0.05). Animal weight also showed significant changes in 45 mg and 90 mg groups in comparison with the control group (p<0.01). This study showed that at least administration of more STZ in short period might have more effect and causes more imbalances in cells turnover. The results of this study were in accordance with other qualitative and quantitative surveys. Moreover, it was suggested that in the early stages of the induced diabetes mellitus by STZ, the inducer has different effects and more doses may cause more induction and effects on kidneys.