URINARY-EXCRETION OF PROSTAGLANDINS AND ELECTROLYTES IN DEVELOPING-CHILDREN

A longitudinal study of the urinary excretion of prostaglandin (PG) E and PGF.alpha. was performed in 55 healthy children aged from 1-114 mo. In addition, the urinary PG and electrolytes were studied in 6 children with Bartter''s syndrome before and after an oral treatment with indomethacin. In normal children, both urinary PGE and PGF.alpha. increased with age, more markedly before 24 mo. of age. During this period, a positive and significant correlation was found with the urinary osmolality (r = 0.61, 16, P < 0.05 for PGE; r = 0.82, 16, P < 0.001 for PGF.alpha.). At every age, the urinary PG were related to the K excretion (r = 0.68, 55, P < 0.001 for PGE; r = 0.65, 55, P < 0.001 for PGF.alpha.) but not to the natriuresis. In children with Bartter''s syndrome, the increased urinary excretion of PGE, PGF.alpha. and K was consistently reduced after indomethacin treatment when the natriuresis was either decreased or increased after treatment. The renal PG might play a role in the control of K excretion by the kidney. The determination of normal values in different age groups appears necessary for an accurate interpretation of the urinary PG.