Indomethacin induced hypotension in sodium and volume depleted rats.

After a single oral dose of 4 mg/kg indomethacin (IDM) to sodium and volume depleted rats plasma renin activity (PRA) and systolic blood pressure fell significantly within four hours. In sodium repleted animals indomethacin did not change systolic blood pressure (BP) although plasma renin activity was decreased. Thus, indomethacin by inhibition of prostaglandin synthesis may diminish the blood pressure maintaining effect of the stimulated renin-angiotensin system in sodium and volume depletion.