Abstract
Since a specific inhibitory activity against gastric secretion was found in the submaxillary glands of mice, an attempt was made to extract and purify the active substance. An aqueous extract of the submaxillary glands of adult male mice was purified by a successive process in the order of gel filtration on Sephadex G-100, column chromatography on DEAE-cellulose, and a second gel filtration on Sephadex G-100. This process resulted in a higher purified fraction (Frac. 4B), which exhibited an enhanced activity 100 times that of the crude extract. This fraction was still proved to contain a small amount of contamination by electrophoresis, but the activities of protease, histaminase, and kallikrein werenegligible. However, this fraction showed esterase activity 3.2 times that of trypsin. The antisecretory activity was lost by proteolysis or heat treatment. The active substance was assumed to be a protein having a molecular weight of about 50000 from the result of gel filtration. In the antisecretory activity of the active substance obtained from the submaxillary galnds, definite sexual dimorphism like the case of nerve growth factor (NGF) and esterase was not recognized.
