Increased urinary 6-keto-PGF1 alpha excretion during water immersion is blunted by metoclopramide in normal man.
Urinary excretion of 6-keto-PGF1 alpha and 2,3 dinor-6-keto-PGF1 alpha, as indices of the renal and systemic production of prostaglandins, was measured during water immersion in a group of 6 healthy volunteers both in the presence and absence of dopamine blockade by the dopamine receptor antagonist, metoclopramide. Urinary flow rate and excretion of both sodium and 6-keto-PGF1 alpha increased during water immersion, while plasma renin activity and plasma aldosterone were reduced. Urinary kallikrein and 2,3 dinor-6-keto-PGF1 alpha also tended to increase during water immersion. Administration of metoclopramide significantly reduced 6-keto-PGF1 alpha and sodium excretion during water immersion, but produced no changes in plasma renin activity or in 2,3 dinor-6-keto-PGF1 alpha. Plasma aldosterone concentrations after metoclopramide were similar to those observed in the pre-immersion period. An increased synthesis of the vasodilator and natriuretic prostacyclin in the kidney might play a role in the response to water immersion. The reduced sodium and 6-keto-PGF1 alpha excretion observed after metoclopramide administration suggests that dopamine might induce prostacyclin synthesis in the kidney during water immersion.
Minuz
P
P
Istituto di clinica Medica, Università di Verona, Italy.
Coruzzi
P
P
Paluani
F
F
Ravanetti
C
C
Lechi
C
C
Delva
P
P
Lechi
A
A
Novarini
A
A
D015121:6-Ketoprostaglandin F1 alpha / Q000652:urine*; D000328:Adult; D000450:Aldosterone / Q000097:blood; D001794:Blood Pressure; D011464:Epoprostenol / Q000096:biosynthesis; D006339:Heart Rate; D006801:Humans; D007101:Immersion / Q000503:physiopathology*; D007610:Kallikreins / Q000652:urine; D008297:Male; D008787:Metoclopramide / Q000494:pharmacology*; D011863:Radioimmunoassay; D012083:Renin / Q000097:blood
D000450:Aldosterone; D015121:6-Ketoprostaglandin F1 alpha; D011464:Epoprostenol; D007610:Kallikreins; D012083:Renin; D008787:Metoclopramide