A bio-assay and histochemical study of antidiuretic hormone in adrenalectomized rats

Abstract

This study is an attempt to shed some light on the complex interrelationship between the hypothalamico-neurohypophyseal system and the adrenal cortex in control of mammalian water balance. Bio-assays of plasma antidiuretic hormone levels have been combined with densitometric estimations of the amount of histochemically stainable secretory substance in the neurohypophysis. Determinations were made at various intervals after bilateral adrenalectomy, as well as on unoperated control animals. Both types of determinations revealed considerable variation in antidiuretic hormone during the period of developing adrenal insufficiency. Several new techniques applied to this problem in the present study have yielded, it is felt, more precise information than has been obtainable in similar previous studies utilizing less specific methods.