1. The daily urine excretion has been studied of prostaglandins (PG) E2 and F2α, as measured by radioimmunoassay, in eight children and seven adults with Bartter's syndrome.
2. Excretion of both PGE2 and PGF2α was significantly higher in the patients with Bartter's syndrome than in 17 normal children.
3. Twelve normal adults excreted significantly more PGE2 and PGF2α than did the normal children. In contrast, adults with Bartter's syndrome did not show an increase in prostaglandin excretion.