Evidence for sodium specificity of the receptors in the fourth cerebral ventricle affecting sodium excretion in the cat.

Perfusion of the fourth cerebral ventricle with artificial cerebrospinal fluid, made hypertonic by the addition of 0.89 M sucrose, resulted in no change in the rate of renal sodium excretion. These data lead us to conclude that the putative receptive field in the area of the fourth ventricle which is capable of affecting urinary sodium excretion contains elements that are sodium-specific