| Abstract: | In 5 experiments acute absolute body-fluid deficits were induced in a total of 36 male albino Sprague-Dawley rats by injection of the diuretic drug furosemide, which caused up to 20% reduction of extracellular fluid volume and up to 2% reduction of intracellular fluid volume. Water and .3 M NaCl were subsequently made available to allow the Ss to replace their body fluids by drinking. The Ss increased their intake of both fluids, but replaced less than half of the total deficit, thereby tolerating larger and larger voluntary body-fluid deficits as the size of the diuretic fluid loss increased. Plasma measures showed that the Ss sustained hypovolemia after drinking, while intracellular fluid volume was apparently restored. Fluid-depleted Ss drank normally in response to intracellular dehydration induced by a sodium chloride load. Results demonstrate that incomplete restoration of body-fluid balance after body-fluid depletion is due to a failure to drink in response to extracellular dehydration. (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) |
