Collagenase activity of rat kidney with glomerulonephritis during the heterologous phase

By means of a biological assay the collagenolytic activity of kidneys from rats with Masugi type glomerulonephritis in the heterologous phase and organs from control animals that were given normal heterologous serum was tested. Collagenolysis was found in both examples, but there wre quantitative and qualitative differences in the collagenase activity. In kidneys from animals with Masugi nephritis we found higher activity than in the controls. Normal rat serum inhibits the enzymatic process at a mean percentage of 9.1% whereas EDTA, a selective inhibitor of granulocytic collagenase inhibited the reaction up to 34%. It is concluded that this collagenolytic system is involved in the pathogenesis of the disease by degrading the structural associated collagen of the glomerular basement membrane.