Elevated 1,25-dihydroxyvitamin D3 and intestinal calbindin-D9k in the toothless rat
| Autor: | M. F. Seifert, R. W. Gray, M. E. Bruns |
|---|---|
| Rok vydání: | 1990 |
| Předmět: |
Vitamin
Aging Calbindins medicine.medical_specialty Duodenum Physiology Endocrinology Diabetes and Metabolism chemistry.chemical_element Rickets Biology Calcium Muscle Development Rats Mutant Strains Bone resorption chemistry.chemical_compound S100 Calcium Binding Protein G Calcitriol Physiology (medical) Calcium-binding protein Internal medicine medicine Vitamin D and neurology Animals Calcifediol Tooth Abnormalities Body Weight Muscle Smooth Phosphorus Metabolism medicine.disease Vitamin D-dependent calcium-binding protein Rats Endocrinology chemistry |
| Zdroj: | American Journal of Physiology-Endocrinology and Metabolism. 258:E377-E381 |
| ISSN: | 1522-1555 0193-1849 |
| DOI: | 10.1152/ajpendo.1990.258.2.e377 |
| Popis: | The toothless (tl) rat is a nonlethal osteopetrotic mutation characterized by systemic skeletal sclerosis, growth plate morphology suggestive of rickets, and morphological evidence of reduced osteoclastic bone resorption. Vitamin D metabolites, serum calcium and phosphorus levels, and the developmental appearance of vitamin D-dependent intestinal calcium binding protein (calbindin-D9k) was studied in normal and mutant rats of tl stock from 7 to 35 days of age. 1,25-Dihydroxyvitamin D3 [1,25-(OH)2D3] was found to be significantly elevated in mutant animals by 7 days of age (71 +/- 9 pM, tl/tl vs. 24 +/- 8 pM, +/?) and continued to increase to a peak of 428 pM at the time of weaning. This was 240% higher than normals at this period. The elevated levels of 1,25-(OH)2D3 stimulated a significant and precocious appearance of intestinal calbindin-D9k in mutants, beginning by 14 days of age and reaching their peak levels at 21 days postpartum (25.6 +/- 1.7 micrograms/mg protein, tl/tl vs. 16.4 +/- 1.5 micrograms/mg protein, +/?). The cause of the elevated circulating levels of 1,25-(OH)2D3 in tl rats is unknown but may be due to the low serum phosphorus levels present in these animals. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|