Skeletal buffering of acute metabolic acidosis
Bettice, J.A.; Gamble, J.L.
American Journal of Physiology 229(6): 1618-1624
1975
ISSN/ISBN: 0002-9513 PMID: 1211494 Document Number: 95875
Female dogs weighing 8 to 14 kg were given 24Na by vein and male Sprague-Dawley rats were given 22Na by mouth to label their bones before they were given HCl by infusion to produce acute metabolic acidosis. There were significant reductions in skeletal Na within the first 5 h of acidosis which could be only partly attributed to the hyponatraemia which accompanied the infusion of HCl. Decreases were greatest in the smaller bones of the rat; in the dog, losses from flat bones exceeded those of long bones. Only the rapidly exchangeable Na of bone was involved in the changes due to acidosis. During experiments lasting 1.5 h, the skeletal losses were small and could be ascribed almost entirely to the decrease in the amount of Na contained in bone water. After 5 h the amount of Na released from the skeleton was sufficient to account for much of the tissue buffering.