Interactions of renal prostaglandins, renin-angiotensin system and renal kallikrein-kinin system in human hypertension.

Dietary sodium deprivation lowered blood pressure in patients with essential hypertension, while indomethacin induced a rise in blood pressure with significant decreases in plasma angiotensin II concentration and urinary excretion of sodium and PGE. In contrast, captopril lowered blood pressure in them with significant decrease in plasma angiotensin II concentration and significant increase in urinary excretion of sodium and PGE. These data strongly indicate that the decreased PG generation in the nephron could elevate blood pressure by means of sodium retention caused by the reduced renal excretory function in spite of the decreased R-A system in human, suggesting the involvement of renal tubular PGE2 in the regulation of blood pressure.