Effects of continuous subcutaneous insulin infusion on renal morphology in experimental diabetes. II. Glomerular...

Stereological studies were performed on renal glomeruli from control rats, untreated streptozotocin-diabetic rats and diabetics treated by subcutaneous infusion of insulin for 16 weeks. Estimates of glomerular basement membrane thickness were obtained by dividing membrane volume by membrane surface area. In addition, arithmetic and harmonic mean thicknesses were calculated from orthogonal intercept lengths, and used to provide information on the variability of basement membrane thickness. In untreated diabetics, both arithmetic and harmonic mean thicknesses were significantly greater than values found in control animals. The thickening of the basement membrane appeared to be generalized rather than markedly focal. All thickness variables were normalized by insulin infusion therapy. These findings underline the importance of good glycaemic control and early intervention in experimental diabetes and one of its main complications.