Electrolyte Balances Following Total Body X-Irradiation

Abstract

One of the prominent features of irradiation sickness is the attendant upset of salt and water metabolism. Depending upon the species, this may be manifested in the forms of vomiting, diarrhea, and diuresis. An exact determination of the changes in electrolyte balance following total body x-irradiation is, therefore, of interest. Methods. Twenty 250 g male white rats (Rolfsmeyer Co., Madison, Wisconsin) were placed in metabolism cages over siliconized glass funnels, and allowed free access to distilled water and a diet containing 60% sucrose, 18% lactalbumin, 16.9% Crisco, 4% modified Wesson salt mixture (minus its Na⁺, K⁺, and Cl), 1% liver extract (Wilson Co., liver fraction D. Lot 41863), 0.1% choline hydrochloride, with supplements of thiamine, pyridoxine, riboflavin and calcium pantothenate. Roughly 5% of the Na⁺, K⁺, and Cl intake was furnished by the diet; coming largely from the liver extract. The remainder of the sodium and potassium chlorides was administered daily by intraperitoneal injection. In the control period the average total electrolyte intake was 1.55 meq of sodium. 2.37 meq of potassium, and 2.54 meq of chloride per 48-hour period. Under these conditions the electrolyte intake was largely independent of the level of food intake. Each 48 hours, the food intake and body weight were recorded, and the excreta were removed for analysis. The excreta were collected quantitatively in barium hydroxide solution, evaporated to dryness, and ashed at 500°C for 12 hours. Sodium and potassium determinations were made on food, injection solutions, and excreta, with a flame photometer attachment to the Beckman DU Spectrophotometer. Chlorides were determined on the same samples by the Volhard method.