Suppressive effect of 1,25-dihydroxyvitamin D3 on circulating parathyroid hormone in acute renal failure.
To elucidate whether the kidney hormone 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3) directly feedback regulates the secretion of parathyroid hormone (PTH), 10 patients with acute oliguric renal failure were studied. Serum ionized calcium (Ca++) was kept constant and subnormal by continuous peritoneal dialysis with low Ca++ dialysis fluid. In the control period (24 h), PTH was found to be constantly increased. In the treatment period (30 h), five patients received 250 ng 1,25-(OH)2D3 iv every 6 h, while five comparable patients served as controls. A significant suppression of PTH-levels was observed in the treatment group after a lag-period of 12-18 h during stable low Ca++. In the control group, PTH remained constantly increased throughout the trial. Since Ca++ was kept constant by the dialysis procedure, the observed reduction of PTH-levels cannot be explained by the calcemic effect of 1,25-(OH)2D3. The data suggest that 1,25-(OH)2D3 directly feedback regulates PTH secretion in humans with normal parathyroid glands.
D058186:Acute Kidney Injury / Q000097:blood*; D000328:Adult; D000368:Aged; D002117:Calcitriol / Q000494:pharmacology*; D002118:Calcium / Q000097:blood; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood*
D010281:Parathyroid Hormone; D002117:Calcitriol; D002118:Calcium