Effect of treatment with 17 α-alkylated androgens on C4 conversion products in hereditary angioedema studied by crossed immunoelectrophoresis

Abstract

During agarose electrophoresis C4 in normal human serum is converted into cleavage products of β1 and β2 mobility. By contrast in the serum of untreated patients with hereditary angiodema C4 gives only one β2 peak on crossed immunoelectrophoresis. The normal C4 electrophoretic pattern is restored in serum of patients treated with stanazolol but not with danazol despite the same C1-esterase inhibitor (C1 INH) activities and C4 serum concentrations. We suggest that stanazolol besides having specific effect on C1 INH activity can interfere with other protease inhibitors affecting C1 activation.