Glucocorticoids Increase Amylase mRNA Levels, Secretory Organelles, and Secretion in Pancreatic Acinar AR42J Cells

摘要: Previous studies have suggested a role for glucocorticoids in the differentiation of acinar pancreas. We now used rat tumor cell line AR42J, derived from pancreas, to directly study this effect vitro. The steroid hormones dexamethasone, corticosterone, aldosterone, and progesterone, but not estrogen, increased both amylase content number secretory granules these cells. potencies steroids were related their effectiveness as glucocorticoids; dexamethasone was most potent hormone gave maximal effects at 100 nM. Morphometric analyses revealed that volume density 5.5-fold 0.20 +/- 0.08 1.10 0.20% (n = 4) cytoplasmic volume. Dexamethasone treatment also rough endoplasmic reticulum 2.4-fold 1.20 0.09 2.86 0.30% 5) After 48 h cellular increase eightfold 2.8 0.4 22.6 3.8 U/mg protein 6). This discernible after 12 incubation approached stimulation 72 incubation. increases due synthesis shown by specific immunoprecipitation [35S]methionine-labeled proteins. Moreover, vitro translation mRNA indicated mRNA. led secretion response secretagogue cholecystokinin. These data indicate, therefore, induce more highly differentiated phenotype AR42J pancreatic cells, they suggest act via enhanced transcription mRNAs