Abstract
PGE2 has an established role in renal water handling. The present study was undertaken to examine the role of microsomal prostaglandin E synthase-1 (mPGES-1) in the diuretic response to acute and chronic water loading. Compared with wild-type (+/+) controls, mPGES-1 -/- mice exhibited impaired ability to excrete an acute, but not chronic water load. In response to acute water loading, urinary PGE2 excretion in the +/+ mice increased at 2 h, in parallel with increased urine flow. In contrast, the -/- mice exhibited a delayed increase in urinary PGE2 excretion, coinciding with the stimulation of renal medullary mRNA expression of cytosolic prostaglandin E synthase but not mPGES-2. At baseline, renal aquaporin-2 (AQP2) expression in mPGES-1 -/- mice was enhanced compared with the +/+ control. In response to acute water loading, renal AQP2 expression in the +/+ mice was significantly reduced, and this reduction was blunted in the -/- mice. Despite striking changes in AQP2 protein expression, renal AQP2 mRNA in both genotypes largely remained unchanged. Overall, these data support an important role of mPGES-1 in provoking the diuretic response to acute water loading.
Original language | English (US) |
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Pages (from-to) | F1129-F1135 |
Journal | American Journal of Physiology - Renal Physiology |
Volume | 296 |
Issue number | 5 |
DOIs | |
State | Published - May 2009 |
Keywords
- Aquaporin-2
- Collecting duct
- Diuresis
- Water loading
ASJC Scopus subject areas
- Physiology
- Urology