HISTOCHEMICAL DEMONSTRATION OF INTESTINAL GLYCOSIDASES IN THE NEONATAL RAT
FORT DETRICK FREDERICK MD
Pagination or Media Count:
Indolyl substrates for Beta-D-galactosidase, Beta-D-glucuronidase, Beta-D-fucosidase, and Beta-D-glucosidase have been used to detect specific enzymatic activity in frozen sections of rat intestine. The animals ranged in age from newly born to 28 days. Specimens obtained from fetal, normal adult, and adult germ-free rats were used for controls. Reactions for all enzymes were demonstrated both in the epithelial cytoplasm and in reticular cells of the lamina propria. In the jejunum and ileum minimal reactivity for galactosidase pH 5.4 in the mucosa was present at birth, but increased to high levels by the 4th day. After the 14th day it decreased again to adult levels. Prominent mononuclear cell staining was noted from late gestation through the neonatal period it decreased somewhat thereafter. In contrast, activity in the colon was less intense, developed more slowly, and decreased less after weaning. Reticular cell reactions in sections incubated at more acid pH values were diminished, and at Ph 2.2 only epithelial staining was noted. Glucuronidase activity was similar to that of galactosidase. Reactions for fucosidase and glucosidase were prominent in reticular cells but positive reactions were confined to the jejunum. The reactions in sections from germ-free animals were, in general, similar to those in specimens from 1-week-old animals. The histochemical reactions confirm previous data based on homogenate assays. The different pattern of development of glycosidase activity in mononuclear cells, however, suggests the presence of isoenzymes with potentially different functions.