Development of Jejunoileal Differences of Activity of Lactase, Sucrase and Acid β-Galactosidase in Isografts of Fetal Rat Intestine

Publisher Website
Google Scholar
Abstract
Jejunal and ileal segments from preterm rat fetuses were implanted under the kidney capsula of adult rats. Sucrase, lactase and acid β-galactosidase activities were determined in the isografts at different times after implantation, and in corresponding segments developing in situ. Whereas fetal intestine contains considerable activity of acid (β-galactosidase and lactase, no sucrase activity is detectable. Similarly – as in situ – 4 weeks after the implantation the jejunal segment exhibited higher activity of sucrase and lactase than the ileal segment. Acid β-galactosidase was more active in ileal than in jejunal segments – both growing in situ as well as isografts. Experiments have thus demonstrated that the expression of the jejunoileal gradient of activity of the 3 enzymes studied does not depend on direct contact with food or gastric, pancreatic and biliary juices. This gives validity to the suggestion that the gradient may already be programmed in fetal intestinal tissue, but other factors active in situ might be responsible for its magnitude.