Proteolytic activity of the gastro-intestinal Mucosa of rabbit

Summary

• 1. Besides pancreas trypsin, a second protease (Tissue Tryptase) is distributed widely in the gastro-intestinal mucosa of rabbit. Its activity is stronger in mucosa of stomach or of small intestine than in those of large intestine and blind intestine. Tissue Tryptase should be differentiated from Pancreas Trypsin and also from Tissue Ereptase. Tissue Ereptase activity is, contrary to that of Tissue Tryptase, stronger in mucosa of large or blind intestine than in that of stomach or of small intestine.

• 2. Pancreas Trypsin and Pancreas Ereptase are found only in mucosa materials from small intestine and missed in those of stomach, blind and large intestine: These activities can be diminished when mucous substances are removed by washing with water.

• 3. Distributions of these enzymes in mucosa of small intestine are as follows: Tissue Tryptase is stronger in the middle part than in the other parts, and Tissue Ereptase is found uniformly distributed over the whole length of small intestine. Pancreas Ereptase and Pancreas Trypsin are weakest in the uppermost part. It seems that they undergo some inactivation by hydrochloric acid in gastric juice. They are strongest in part II and then decrease their activities gradually from oral anal-ward.

• 4. Physiological significance of these enzyme activities is briefly suggested.