Glycogen
accumulation in the renal tubules could be attributed to
hyperglycaemia induced by streptozotocin-induced diabetes.
Ren et al. reported marked enlargement of kidney weight/
body weight (KW/BW), tubulointerstitial fibrosis and
fibronectin in streptozotocin-induced diabetic rats from 8 to
16 weeks. Activin betaA, mainly located in tubular epithelial
cells, was significantly higher in diabetic groups than that in
the non-diabetic groups.