EARLY CHANGES OF KIDNEY MORPHOLOGY AND FUNCTION IN STREPTOZOTOCIN-INDUCED DIABETIC RATS

In order to study the nephropathy associated with experimental streptozotocin diabetes, serial functional and ultrastructural studies were done in insulin-treated (Group T), untreated (Group D) diabetic Wistar rats and normal controls on d 3, d 8, d 14 and d 28 of diabetes. The ratio of kidney weight to the body weight (KW/BW) and mean glomerular diameter (MGD) in diabetes rats at varying durations were increased as compared with those in control animals, but an increase of KW/BW and MGD in Group D was more marked than in Group T. The creatinine clearance (Ccr) and total urinary protein excretion rate (TUPER) were increased in Group D end T, but the increase in TUPER appeared later in Group T than in Group D. Enlargement of epithelial cells, disappearance of folds on their surface and widening of foot processes were observed after 3 d of diabetes. After 14 d of diabetes, increased basement membrane-like material in the mesangium was found. Morphologically an increase in glomerular size, expanded foot processes with ball-like terminal expansions, thickened basement membrane were observed.