title: Stimulation of 1,25-dihydroxyvitamin D production by parathyroid hormone and hypocalcemia in man.
abstract: The serum levels of 1.25-dihydroxycholecalciferol [1,25(OH)2D3] were increased in five patients with primary hyperparathyroidism [60 +/- 13 (SD) pg/ml; normal value, 33 +/- 15 (SD) pg/ml] but fell rapidly after parathyroidectomy to values of 23 +/- 9 (SD) pg/ml. This was accompanied by parallel decreases in the serum concentrations of calcium and immunoreactive parathyroid hormone. Over the following 5--35 days, the serum 1,25(OH)2D3 concentrations increased markedly to levels of 59 +/- 17 (SD) pg/ml, which could most likely be explained by a stimulatory effect of the hypocalcemia per se on the renal production of 1,25(OH)2D3.
mesh_terms: D000368:Aged; D002117:Calcitriol; D002118:Calcium / Q000097:blood; D004100:Dihydroxycholecalciferols / Q000096:biosynthesis* / Q000097:blood; D005260:Female; D006801:Humans; D006887:Hydroxycholecalciferols / Q000096:biosynthesis*; D006961:Hyperparathyroidism / Q000097:blood / Q000601:surgery; D006996:Hypocalcemia / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010280:Parathyroid Glands / Q000601:surgery; D010281:Parathyroid Hormone / Q000502:physiology*
chemical_list: D004100:Dihydroxycholecalciferols; D006887:Hydroxycholecalciferols; D010281:Parathyroid Hormone; D002117:Calcitriol; D002118:Calcium