Central Localization of the Osmotic Control Center

¹ From the Aero Medical Laboratory, Wright Air Development Center, Wright-Patterson Air Force Base, Ohio

Intracarotid injections of hypertonic solutions cause marked antidiureses in lightly chloralosed dogs. Intrafemoral injections of identical solutions of hypertonic saline and urea were done with resulting slight diureses, reflex flexing of the leg and increased urine osmolarity. Femoral artery injections of hypertonic sodium sulfate are followed by antidiureses which are explained, at least partially, by active reabsorption of the sulfate ion in the proximal renal tubules. The absence of evidence of antidiuretic activity following intrafemoral artery injections and the marked antidiuretic effect demonstrated following intracarotid injections lends support to the theory of central localization of the osmotic control center.