The mechanism of end-organ resistance to 1α,25-dihydroxycholecalciferol in the common marmoset

摘要: The common marmoset, a New World monkey, requires large amount of cholecalciferol (110 i.u./day per 100g body wt.) to maintain its normal growth. In previous report, we demonstrated that the circulating levels 1 alpha, 25-dihydroxycholecalciferol [1 alpha,25(OH)2D3] in marmosets are much higher than those rhesus monkeys and humans, but not hypercalcaemic [Shinki, Shiina, Takahashi, Tanioka, Koizumi & Suda (1983) Biochem. Biophys. Res. Commun. 14, 452-457]. To compare effect daily intake cholecalciferol, two were given (900 wt). Their serum calcium, 25-hydroxycholecalciferol 24R,25-dihydroxycholecalciferol markedly elevated, alpha,25(OH)2D3 remained within range similar fed diet (intake 5 Intestinal cytosols prepared from both contained 3.5 S macromolecules which was bound specifically. However, only one-sixth as many receptors monkeys. Furthermore, activity alpha,25(OH)2D3-receptor complex binding DNA-cellulose very low marmosets. These results suggest marmoset possesses an end-organ resistance is useful animal model for studying mechanism vitamin D-dependent rickets, type II.