The Rate and Total Loss of Body Water on the Survival Time of Adrenalectomized Frogs. ∗ †

Abstract

Summary

All frogs employed in this study may be conveniently divided into 4 groups (18-22 animals/group): the adrenalectomized frogs whose postoperative body weights were either controlled, to within ± 1.5 g of their individual pre-operative values, or uncontrolled; and the controls, both renal damaged and unoperated frogs. The individuals of each group were subjected to a constant dehydrating force and the resulting data were statistically analyzed with respect to the following points: a, the rate of loss and b, the total loss of body weight (water) and c, the duration of survival on exposure to a constant force of dehydration.

1. A comparison of the difference between respective means of the 2 groups of adrenalectomized frogs shows no significance as regards the foregoing items a, b, and c. 2. Comparison between the 2 groups of controls (renal damaged and unoperated frogs) gives no significance with respect to items b and c, though it does for a. 3. A comparison between the respective means for either group of adrenalectomized frogs and their controls (renal damaged) produces a significance for a and b, and for c as it affects the death point of the controlled but not of the uncontrolled adrenalectomized frogs. 4. On the basis of the known cardiovascular embarrassment subsequent to adrenalectomy, it is suggested that the increased osmotic pressure resulting from the forced water loss and the attendant decrease in peripheral circulation brings an increased osmotic stress to bear on an already weakened heart action. It is suggested that this stress is the deleterious factor in affecting the physiological points raised.