DISSOCIATION OF VOLUME AND OSMOLAR CONTROL OF ADH IN INFANCY.

Abstract

It has been amply demonstrated that there are two physiologic stimuli which control the release of antidiuretic hormone (ADH) from the posterior pituitary. The first, delineated by the experiments of E. B. Verney (1947-1948),1involves alterations in intracellular in osmoreceptor cells which are probably in the supraoptic and paraventricular hypothalamic nuclei. The second and more recently defined stimulus appears to involve isotonic changes in some parameter (s) of the extracellular volume.2-10While the location of the volume receptors is unknown, there is evidence to suggest their locus in the left atrium and adjacent pulmonary venous bed and their communication cephalad via the vagus nerves.8,11-13 Carter et al14have reported a 40-year-old patient with inappropriate secretion of ADH and hyponatremia secondary to head trauma in whom there appeared to be a dissociation of osmolar and control stimuli. In this patient ADH secretion during the early