Glomerular basement membrane synthesis and serum concentration of type IV collagen in streptozotocin-diabetic rats.

Glomerular basement membrane synthesis was measured in vivo in diabetic rats at various times after streptozotocin injection. Simultaneously the type IV collagen concentration in serum was determined by a radioimmunoassay specific for the terminal cross-linking domain, 7S collagen. Basement membrane collagen synthesis and the 7S collagen levels were markedly raised in diabetic animals 18-34 days after streptozotocin injection and showed a significant correlation. The results suggest that the amount of serum 7S collagen reflects increased basement membrane synthesis in a diabetic situation. Both basement membrane collagen synthesis and serum 7S collagen concentration also show a positive correlation with the blood glucose levels of diabetic rats. This indicates that the degree of metabolic dysregulation influences basement membrane synthesis.