Short-term 1,25-dihydroxyvitamin D3 administration raises serum osteocalcin in patients with postmenopausal osteoporosis.

In order to evaluate whether 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] could increase the serum concentration of osteocalcin (BGP) in patients with post-menopausal osteoporosis, we administered 2 micrograms/d of 1,25(OH)2D3 to 14 patients with biopsy proven osteoporosis for two weeks. An additional 13 age and sex-matched patients with osteoporosis received no drug and served as the control. Administration of 1,25(OH)2D3 significantly increased the serum concentration of 1,25(OH)2D from 31 +/- 2 SE to 56 +/- 5 pg/ml (p less than 0.01). Commensurate with the rise in 1,25(OH)2D was a significant increase in BGP from 3.9 +/- 0.6 to 6.4 +/- 0.9 ng/ml (p less than 0.001). There were no significant changes for these parameters in the control group. It is concluded that short term 1,25(OH)2D3 administration is effective in raising BGP concentrations in patients with post-menopausal osteoporosis.