THE EFFECT OF THE INTRAVENOUS ADMINISTRATION OF PITRESSIN ON RENAL FUNCTION IN MAN

¹ The New York Hospital, 525 East 68th Street, New York, New York
² Departments of Physiology and Surgery, New York University College of Medicine, New York, New York

1. The effects on the renal circulation of the intravenous infusion of Pitressin have been examined in eighteen subjects.

2. Physiologic doses (50 to 100 milliunits/hr.) had generally no effect on renal plasma flow or filtration rate; pharmacologic doses caused a moderate reduction in renal plasma flow with a simultaneous reduction in filtration rate of lesser magnitude. The renal hemodynamic changes involve constriction of both afferent and efferent arterioles, predominantly the latter.

3. Antidiuresis was promptly achieved with 0.3 to 0.4 milliunits/hr. per kgm.

4. The degree of antidiuresis bore no relationship to concomitant alterations in renal clearances, supporting the accepted belief that the site of action of Pitressin in the mammal is the renal tubule.

5. It is suggested that these results be used in the re-interpretation of previous studies of the effects of Pitressin on electrolyte excretion in which clearances were not measured.