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PubMed · 3498842

Interactions between calciotropic hormones.

J N Bradbeer
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Abstract

The metatarsal cytochemical bioassay (CBA) for parathyroid hormone (PTH) was adapted to study interactions between PTH and certain vitamin D metabolites. Thus, while they had no effect in the system alone, both 1,25(OH)2D3 and 25(OH)D3 caused a dose-dependent potentiation of PTH-stimulated glucose 6-phosphate dehydrogenase activity in the hypertrophic chondrocytes of the rat metatarsal. 1,25(OH)2D3 was about 1000 times more potent than 25(OH)D3. Specificity is indicated by the lack of a similar effect when either oestradiol or 1,24,25(OH)3D3 or a lactone derivative of 1,25(OH)2D3 was used. Furthermore, the rapidity of the effect of 1,25(OH)2D3 and 25(OH)D3, within 8 minutes, favours a membranophilic mechanism rather than the conventional nuclear mechanism of steroid hormone action.

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24,25-Dihydroxyvitamin D 3AnimalsBiological AssayCalcifediolCalcitriolDihydroxycholecalciferolsFemaleHumansHydroxycholecalciferolsMetatarsusParathyroid HormoneRatsVitamin DJournal Article

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J N Bradbeer. 1987. Interactions between calciotropic hormones.. https://doi.org/10.1177/014107688708000806

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