Research on antidiuretic hormone

Abstract

l°. Experimental data concerning the functional inter- RELATIONS BETWEEN THE POST-PITUITARY AND THE

ADRENAL CORTEX

The authors bring experimental arguments in favour of the antagonism between antidiuretic hormones and cortieo- adrenal hormones in respect with hydro-mineral metabolism.

They indeed studied the hydric and ionic metabolism in dogs which had been subjected successively :

— to section of the supra-optico-pituitary tractus with re- sulting diabetes insipidus,

— to bilateral ablation of the adrenal gland, — or to the two interventions in inverse order

Such experiments inade it possible to define the part of the adrenal cortex in experimental diabetes insipidus and thatof the andidiuretic hormonc in experimental adrenal insuf- ficiency ; they demónstrate that those disturbances, which re- sult from experimental removal of one of the two endocrine systems ensuring the regulation of the hydromineral metabo- lism, are also indicative of the hyperactivity of the system left intact.

Observation of animáis deprived of both anti-diuretic and cortico-adrenal hormones reveáis the existence of a new ba­ lance characterized by the scarcity of signs in relation to the supression of cither of these two endocrinous factors. Animáis which werc opcrated on in this way show a marked susceptibility to cortical hormones, as minimal doses of these could ensure thcir survival. Bul the balance thus obtained remains uiisteady.

These experiments, which evoke those from Houssay on the antagonism between the ante-pituitary and the páncreas, are susceptible of defining the correlation between the anti- diuretic hormones and the cortico-adrenal hormones.

2º. Role oe ADH in polyuria following distention OF THE LEFT ATRIUM

The distention of the left atrium in the dog provokes an augmentation of diuresis. This distentiou has no effect in the dog deprived of ADH by hypothalamic lesión. This diuresis is accompanied by a reduction in the antidiuretic potential of the blood. The afferent fibers concerned in this neuro-hormonal reflex are located in the vagus nerve.

3º. Favorable effect of posterior-pituitary extracts ON HYPERNATREMIA

The adaptation of animáis and man, driuking only sea water, is facilitated bjr administraron of post-pituitary extracts. These extracts increase the elimination of sodium, reduce thirst, and prolong survival.