[Role of the prostaglandin-kinin system of the kidneys in the transport of sodium and water].

The renal content of prostaglandins A, E and F2, was determined by radioimmunoassay in 33 Wistar male rats, following a preliminary purification and separation of these substances by way of chromatography. At the same time, kallikrein excretion in the urine was determined in the same animals by estimating the etherase activity of the enzyme. Several renal function parameters characterizing sodium and water transport were also analyzed. Thirteen animals were receiving Indometacine, 5 mg/kg for 5 days. In the kidneys of those animals who were kept on a routine water-salt regimen certain quantitative relationships were established between prostaglandins of different types and the activity of the renal kallikreinkinin system. Indometacine, when employed in the above dosage, caused synthesis inhibition of prostaglandins A and E, predominantly, and a significant reduction of the kallikrein activity in the urine. These changes in the humoral state of the kidneys under the effect of Indometacine were accompanied by a reduction of diuresis and natriuresis and of the concentration function of the kidneys. The obtained data emphasize the importance of the prostaglandin-kinin system of the kidneys in water and sodium transport.