HYPOXIC EFFECTS ON THE EXPRESSION OF MINERALOCORTICOID AND GLUCOCORTICOID RECEPTORS IN HUMAN RENAL-CORTEX EPITHELIAL-CELLS

The effects of both mild and severe hypoxic conditions on the expressi on of mineralocorticoid receptor (MR) and glucocorticoid receptor (GR) in the primary human renal cortex epithelial cells (RCEC) were invest igated. Slot blot analyses were performed with human beta-actin cDNA a nd the cDNA probes for unique regions of MR and GR. The steady-state m RNA level of the house-keeping beta-actin gene remains the same in RCE C under either normoxic or hypoxic conditions. However, there was a 45 % reduction in MR expression and a 30% increase in GR expression, unde r mild hypoxic condition (15% O-2) over 3 days. Furthermore, cells sub jected to a severe hypoxic condition (0.5% O-2) for 24 hours exerted a 22% reduction in MR expression and a 64% increase in GR expression. C hanges in MR and GR expression may, in part, explain the physiological changes in adrenal cortical function observed in hypoxic conditions. (C) 1996 Academic Press, Inc.