[Compensatory reactions of the kidneys to orthostatic effects]

Studies of orthostatic effects on the renal hemodynamics and excretory function of the dog showed an increase in the heart rate, a fall in the arterial and venous pressure and a decline of the Na and K concentrations in the urine. The studies demonstrated that changes in the renal excretory function were a compensatory hemodynamic reaction to the gravity effect associated wtih an alteration of the body position in space.