Normal plasma arginine esterase and the Hageman factor (factor XII) -prekallikrein-kininogen system in cystic fibrosis.

Previous investigators have suggested that the biological activity of plasma prekallikrein is defective in cystic fibrosis. In contrast, no such difference was demonstrable between normal and cystic fibrosis plasma. Esterolytic activity for the synthetic substrate p-toluene sulfonyl-arginine methyl ester (TAMe) evolved normally in cystic fibrosis plasma treated with chloroform and ellagic acid, a measure of generation of plasma kallikrein. Additionally, plasma prekallikrein (Fletcher factor) and high molecular weight kininogen (Fitzgerald factor), a substrate of plasma kallikrein, were normal. Thus, the concept that cystic fibrosis is associated with abnormalities in the plasma kallikrein-kinin system could not be supported.