COMBINED EFFECTS OF ALDOSTERONE, VASOPRESSIN, AND CORTICOSTERONE ON SALT AND WATER DISTRIBUTION IN THE NEUROHYPOPHYSECTOMIZED ADRENALECTOMIZED RAT

Abstract

The interaction of aldosterone, vasopressin, and corticosterone on salt and water distribution was examined in the neurohypophysectomized adrenalctomized rat by use of conventional partition methods. When aldosterone and vasopressin are given in combination, they act in opposition and sodium is gained or lost depending on which is dominant. Similarly, the desalting effect of corticosterone can blunt or even reverse the sodium-accumulating effect of aldosterone. When all three hormones are given together the salt-losing effects of vasopressin and corticosterone are not additive. Instead, the administration of a modest amount of vasopressin in the presence of aldosterone and corticosterone results in a combination which favors, in the muscle, significant sodium accumulation and potassium loss. These findings indicate that the result obtained on administration of any one of these three hormones to the intact animal depends on the homeostatically adjusted levels of the other two.