Influence of vitamin D on bicarbonate reabsorption.

The effects of acute administration of 25 hydroxycholecalciferol on bicarbonate reabsorption was studied in dogs. 25 hydroxycholecalciferol infused into the renal artery at a dose of 0.2 microgram/kg/hour led to a small but significant bilateral increase in bicarbonate reabsorption in intact dogs. 25 hydroxycholecalciferol had no effect on bicarbonate reabsorption in thyroparathyroidectomized dogs. The phosphaturia of bicarbonate administration was not altered by 25 hydroxycholecalciferol administration.