Control of Proteolytic Activity in Serum: Effect of Soybean Inhibitor in Vivo in the Mouse

Abstract
Soybean inhibitor (SBI) was injected by tail vein into mice of the A strain in single doses of 2.5 to 40 mg. A significant elevation of antiproteolytic titer and decrease in proteolytic activity of the sera was observed in those mice receiving more than 24 mg. of SBI. Significant elevation of the APL titer remained after 7 days. Serial injns. of 20 mg. weekly for 6 wks. resulted in no demonstrable abnormalities in the animals as indicated by observation during life or by post-morten gross and microscopic examination of their organs.