Premium
Induction of rat jejunal epithelial cell expression of sucrase‐isomaltase by glucocorticoids in priimary cell culture and in vivo
Author(s) -
Yeh KwoYih,
Yeh Mary,
Holt Peter R.
Publication year - 1989
Publication title -
biology of the cell
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.543
H-Index - 85
eISSN - 1768-322X
pISSN - 0248-4900
DOI - 10.1111/j.1768-322x.1989.tb00783.x
Subject(s) - biology , cell , cell culture , dna synthesis , plating efficiency , thymidine , in vivo , mitosis , cell division , cell growth , microbiology and biotechnology , cell cycle , medicine , endocrinology , in vitro , biochemistry , genetics
The cell cycle phase that mediates the induction of intestinal sucrase‐isomaltase (SI) expression by glucocorticoids was investigated by measuring migration rates of 3 H‐DNA‐labeled and of SI‐containing epithelial cells by autoradiography and indirect immunofluorescent staining after simultaneous administration of [ 3 H]thymidine and cortisone to 12‐d‐old rat pups. By 24 and 48 h, lead 3 H‐DNA‐labeled cells had migrated 7.8 and 12.4 cell positions higher on the villus than lead cells expressing SI. Cell migration rates from 12 to 24 h and 24 to 48 h were 0.68 and 0.97 cell position/h. Thus, commitment to SI expression occurred in cells 11.5–12.8 h after the S phase, which is calculated to be in the G1 phase. To determine whether committed cells need to replicate to express SI, cell differentiation was examined in primary cultures of crypt cells originating from corticosterone‐treated rats. About two‐thirds of cultured cells were retarded in the S phase after plating, as judged by no increase of DNA labeling indices, no change in epithelial cell number, and the absence of mitosis (<0.01%). The proportion of cells expressing SI increased from 0 to 6–8% between 12 and 24 h, and reached 48% 48 h after plating on collagen‐coated dishes. SI expression did not occur in cells plated on glass or plastic surfaces. Pulse labeling with [ 35S H]methionine confirmed that de novo synthesis of SI occurred in cell cultures. Thus, additional cell cycling of committed cells occuring in vivo is not obligatory for the expression of SI.