1. The role of renal medullary prostaglandin E has been examined in rats with hypertension induced by sodium chloride and deoxycorticosterone (salt—DOC).
2. Synthesis of prostaglandin E was normal in early salt—DOC hypertension. Indomethcin exacerbated the hypertension, and depressed synthesis of prostaglandin E equally in hypertensive and control rats.
3. Synthesis of prostaglandin E was depressed in rats with late salt—DOC hypertension.
4. The results lend support to the concept that prostaglandin E is involved in the regulation of arterial pressure.