Blood Organic Phosphate in Hyperthermic Dogs

Abstract

Abstract : There is a marked fall in plasma inorganic phosphate (P) concentration and urinary inorganic phosphate excretion in unanesthetized dogs exposed to heat. If the fall in plasma inorganic P is due to an increase in metabolism, then one should expect to find an increase in intracellular organic P. The red blood cells, as the most easily obtainable cellular sample, were selected as the yardstick for measuring cellular changes. Acid soluble organic phosphate was determined by the difference between the total P and inorganic P in aliquots of the same sample. Sixteen experiments were conducted on 8 unanesthetized dogs. In a group of 8 dogs exposed to 120F., the whole blood inorganic P fell from a control value of 3.2 to 0.7 mg. percent at the end of 4 hours in a hot room, while the whole blood organic P increased from a control value of 23.1 to 27.2 mg. percent at the end of 4 hours exposure to heat. Six control dogs exposed to 76F air temperature for 4 hours showed no significant changes in whole blood inorganic or organic P.