Concanabalin A-binding glycoprotein fraction in the small intestine and feces of rats.

Abstract

In the previous studies,1>2) in which the mechanisms involved in the toxicity of ingested concanavalin A (Con A) were investigated, we observed the following: 1. The ingested Con A remained unaltered during its passage through the gastrointestinal tract and was rapidly excreted in the faces. 2. It prevented the adaptive responses of the intestinal sucrase, alkaline phosphatase and leucine aminopeptidase activities, which are localized in the brush border membrane, to dietary nutrients. 3. The excreted Con A in the feces was bound to water-insoluble components in the feces, which was suggested by it being released from the feces with an a-methyl-D-mannoside solution but not with water. 4. The water-insoluble components in the feces were confirmed to have an affinity to Con A in vitro. These findings strongly suggested the presence of a Con A-binding glycoprotein in the small intestine and feces of rats.

Origin of Fecal Concanavalin A-Binding Glycoprotein in Rats

“…There was a possible relationship between the excreted amount of fecal CBGP and the CBGP content in the small intestine, but not that in the cecum. 3. The electrophoresis profile of CBGP isolated from the whole small intestine was compatible with that isolated from the luminal surface of the small intestine.…”

“…Thereafter, CBGP could be isolated from the stomach, small intestine, cecum, and feces, in which the amounts of CBGP were found to be much larger in the small intestine than the others, and the origin of fecal CBGP was suggested to be in the small intestine. 3 ) This suggestion, however, further requires the evidence that the fecal CBGP is not derived from intestinal microflora. Thus, this study was undertaken to investigate the presence of CBGP in intestinal microorganisms, and CBGP in the gastrointestinal tract and feces of germ-free rats and that of conventionalized rats.…”

Effects of Dietary Fiber on Fecal Concanavalin A-binding Glycoprotein in Rats

“…They have also demon- The second 15-cm segment from the pylorus. 3 Micromoles of substrate hydrolyzed per hour. (Pooled specimens from four rats.)…”

“…In this connection, the intestinal sucrase activity localized -:;;600 The second 15-cm segment from the pylorus. 3 Micromoles of substrate hydrolyzed per hour.…”

“…Afterwards, CBGP could be isolated from the stomach, small intestine, cecum, and feces, and was found to be at a higher level in the small intestine than in the'others 3 ) and to be localized in its luminal surface. We recently found that CBGP could be isolated from both the feces of germ-free rats and of the conventionalized rats, but not from the intestinal microflora.…”