Decreased glomerular proteinase activity in the streptozotocin diabetic rat.
Decreased glomerular proteinase activity may contribute to matrix accumulation in diabetes. Male Sprague-Dawley rats were rendered diabetic by injection of streptozotocin (STZ) 65 mg/kg i.v.; age-matched, sham-injected rats served as controls. Glomeruli from diabetic rats 1 month after STZ injection demonstrated significant decreases in collagenase and cathepsin B activities compared to control glomeruli. Treatment with insulin resulted in a slight (but not significant) increase in collagenase activity and normalized cathepsin B activity. We conclude that decreased glomerular collagenase and cathepsin B activities are present in STZ diabetes. These alterations may contribute to mesangial matrix accumulation.
Song
R H
RH
Department of Medicine, Veterans Affairs Hospital, Hines, Ill., and Loyola University Chicago Stritch School of Medicine, Maywood, Ill., USA.
Singh
A K
AK
Leehey
D J
DJ
D000818:Animals; D002401:Cathepsin B / Q000378:metabolism*; D017364:Collagenases / Q000378:metabolism*; D003921:Diabetes Mellitus, Experimental / Q000201:enzymology*; D007678:Kidney Glomerulus / Q000201:enzymology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley
D002401:Cathepsin B; D017364:Collagenases