EFFECTS OF HEPARIN AND AMINOGUANIDINE ON GLOMERULAR-BASEMENT-MEMBRANETHICKENING IN DIABETIC RATS

The effects of heparin and aminoguanidine on glomerular basement membr ane thickening were studied in streptozotocin diabetic Sprague-Dawley rats. A placebo-treated group and a non-diabetic group served as contr ols. All diabetic rats remained severely hyperglycaemic (23 mmol/l) th roughout the 8-month study period. At the end of this time relative ki dney weight was significantly increased in diabetic control rats (4.9 +/- 0.5 g/kg b.w.) compared with non-diabetic rats (3.3 +/- 0.3 g/kg). This increase was not affected by the intervention treatments. Glomer ular basement membrane thickness increased 32% in diabetic control rat s (240 +/- 24 nm) compared with non-diabetic rats (182 +/- 20 nm). Thi s increase was prevented by s.c. treatment with both unfractionated an d low molecular weight heparins, while basement membrane thickness was the same in animals treated with oral heparins and aminoguanidine and untreated diabetic rats. Macroscopic malignant kidney tumours were se en in three aminoguanidine-treated rats. In conclusion, subcutaneously administered heparin prevents diabetes-induced glomerular basement me mbrane thickening.