AJP - Gastrointestinal and Liver Physiology, Vol 244, Issue 5 532-G540, Copyright © 1983 by American Physiological Society
Protection of epithelial function in human jejunum cultured with hydrocortisone
J. Scott and T. J. Peters
Over 24-h culture with hydrocortisone (400 nM), activity of brush-border
alkaline phosphatase, alpha-glucosidase, and leucyl-2-naphthylamidase and
cytoplasmic-mitochondrial malate dehydrogenase increased (P less than 0.05)
by 80-133% compared with controls. Uptake of 3-O-methyl-D-[14C]glucose
after 24-h culture was increased (P less than 0.05) by 30% compared with
cultures without hydrocortisone. Labeling of protein with L-[14C]tyrosine
and glycoprotein with D-[3H]glucosamine increased (P less than 0.05) by 40
and 88%, respectively, with hydrocortisone. The effects of hydrocortisone
were dose dependent at normal serum concentrations (100-600 nM) and not
further stimulated by larger concentrations. Cytoplasmic lactate
dehydrogenase and lysosomal hexosaminidase activity, specific radioactivity
of soluble precursor pools for protein and glycoprotein labeling,
incorporation of [3H]thymidine into DNA, and morphology were unaffected by
hydrocortisone. Inhibitors of glucocorticoid receptor binding
(progesterone), mRNA transcription (alpha-amanitin), and protein synthesis
(cycloheximide) prevented the effects of hydrocortisone. We suggest that
hydrocortisone maintains the digestive, absorptive, and cellular function
of cultured human jejunum. These protective effects were associated with
increased protein synthesis and glycosylation and dependent on a classical
steroid-hormone mechanism.
