Vitamin D metabolism in chronic childhood hypoparathyroidism: evidence for a direct regulatory effect of calcium
Carpenter, TO; Insogna, KL; Boulware, SD; Mitnick, MA
| HERO ID | 4947575 |
|---|---|
| In Press | No |
| Year | 1990 |
| Title | Vitamin D metabolism in chronic childhood hypoparathyroidism: evidence for a direct regulatory effect of calcium |
| Authors | Carpenter, TO; Insogna, KL; Boulware, SD; Mitnick, MA |
| Journal | Journal of Pediatrics |
| Volume | 116 |
| Issue | 2 |
| Page Numbers | 252-257 |
| Abstract | We noted the presence of elevated levels of circulating 1,25-dihydroxyvitamin D (83 pg/ml (200 pmol/L), with low total serum calcium concentration (6.5 mg/dl (1.88 mmol/L), in an untreated adolescent boy with hypoparathyroidism. Furthermore, an inverse relationship between total serum calcium and circulating 1,25-dihydroxyvitamin D levels was evident during treatment with 1,25-dihydroxyvitamin D3. We examined this relationship with a 33-hour intravenous infusion of calcium gluconate in the absence of exogenous 1,25-dihydroxyvitamin D3 therapy. The infusion was accompanied by a gradual increase of both total serum calcium and blood ionized calcium concentrations from hypocalcemic to normocalcemic ranges, and produced a 50% reduction in circulating 1,25-dihydroxyvitamin D values, with minimal changes in circulating phosphorus, magnesium, and 25-hydroxyvitamin D values. These results suggest that calcium-dependent, parathyroid hormone-independent regulation of 1,25-dihydroxyvitamin D production may exist in human beings. |
| Pmid | 2299496 |
| Is Certified Translation | No |
| Dupe Override | No |
| Is Public | Yes |
| Language Text | English |