Absence of effect of 24,25-dihydroxyvitamin D3 in primary hyperparathyroidism.
Nineteen patients with primary hyperparathyroidism were treated with 25 micrograms 24,25-dihydroxyvitamin D3 or placebo daily for 3 months according to double-blind cross-over protocol. Serum immunoreactive PTH, total and ionized calcium, urinary calcium excretion, tubular reabsorption of phosphate/glomerular filtrate, and urinary hydroxyproline excretion did not change significantly. Serum 24,25-dihydroxyvitamin D3 levels increased significantly from 1.4 +/- 2.2 (SD) nmol/liter to 38 +/- 11 nmol/liter during the treatment period. Serum 25-hydroxyvitamin D3 and 1,25-dihydroxyvitamin D3 levels did not change. We conclude that pharmacological doses of 24,25-dihydroxyvitamin D3 have no suppressive effect on parathyroid function in primary hyperparathyroidism.
D015650:24,25-Dihydroxyvitamin D 3; D000328:Adult; D000368:Aged; D002118:Calcium / Q000097:blood / Q000652:urine; D004100:Dihydroxycholecalciferols / Q000097:blood / Q000627:therapeutic use*; D004311:Double-Blind Method; D004341:Drug Evaluation; D005260:Female; D005919:Glomerular Filtration Rate / Q000187:drug effects; D006801:Humans; D006887:Hydroxycholecalciferols / Q000097:blood; D006961:Hyperparathyroidism / Q000188:drug therapy* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D010710:Phosphates / Q000652:urine
D004100:Dihydroxycholecalciferols; D006887:Hydroxycholecalciferols; D010281:Parathyroid Hormone; D010710:Phosphates; D015650:24,25-Dihydroxyvitamin D 3; D002118:Calcium