Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

1,25-Dihydroxyvitamin D3 [1,25-(OH)2D3], but not 24,25-(OH)2D3 stimulates the alkaline phosphatase activity of cultured human bone cell populations. The stimulatory effect of the sterol was dose dependent (10(-10)-10(-7) M), evident by 24 h, and observed over a range of cell densities. Analysis of the radiolabeled collagens synthesised by human bone cell cultures indicated the synthesis of predominantly type I collagen. In the presence of 1,25-(OH)2D3, but not 24,25-(OH)2D3, there was a dose-dependent (10(-11)-10(-9) M) increase in radiolabeled proline incorporation into collagenase-digestible protein and in the amount of collagen synthesized, expressed as a percentage of the total protein synthesis. The effect of 1,25-(OH)2D3 was observed over a range of cell densities and appeared to be specific for the synthesis of type I collagen. The stimulatory effect of 1,25-(OH)2D3 on alkaline phosphatase activity and the increase in proline incorporation into collagenase-digestible protein were accompanied by a dose-dependent (5 X 10(-11) to 5 X 10(-8) M) inhibition of bone cell proliferation. These findings suggest that 1,25-(OH)2D3 is an important modulator of the growth and differentiation of human bone cells in vitro. They are also consistent with the possibility that 1,25-(OH)2D3 has direct effects on bone formation in vivo.

Original publication

DOI

10.1210/endo-119-4-1776

Type

Journal article

Journal

Endocrinology

Publication Date

10/1986

Volume

119

Pages

1776 - 1785

Keywords

24,25-Dihydroxyvitamin D 3, Alkaline Phosphatase, Bone and Bones, Calcitriol, Cell Division, Cells, Cultured, Collagen, Dihydroxycholecalciferols, Dose-Response Relationship, Drug, Humans