Tiegs R D, Body J J, Wahner H W, Barta J, Riggs B L, Heath H
N Engl J Med. 1985 Apr 25;312(17):1097-100. doi: 10.1056/NEJM198504253121705.
Calcitonin deficiency has been implicated in the pathogenesis of accelerated bone loss, especially in postmenopausal osteoporosis. To investigate this issue, we studied 25 patients with untreated postmenopausal osteoporosis, 14 age-matched and sex-matched healthy controls (spinal bone mineral density greater than or equal to age-specific and sex-specific mean), and 5 women who had undergone total thyroidectomy. Each subject received an intravenous infusion of 2 mg of elemental calcium per kilogram of body weight over 5 minutes, to test the C-cell secretory reserve. We measured calcitonin by radioimmunoassay in whole plasma and in silica-cartridge extracts of plasma, the latter method providing greatly improved sensitivity and specificity for monomeric calcitonin. Basal immunoreactive calcitonin concentrations, whether measured in whole plasma or in extracts, were significantly higher in the subjects with osteoporosis (P less than 0.01) than in the healthy controls. The calcitonin secretory reserve, as assessed by calcium stimulation, was normal in the osteoporotic group but virtually absent in the thyroidectomy group. We conclude that postmenopausal osteoporosis is not associated with and does not result from calcitonin deficiency. On the contrary, excessive skeletal calcium release may stimulate calcitonin secretion in patients with the disorder.
降钙素缺乏与骨量加速丢失的发病机制有关，尤其是在绝经后骨质疏松症中。为了研究这个问题，我们对25例未经治疗的绝经后骨质疏松症患者、14例年龄和性别匹配的健康对照者（脊柱骨矿物质密度大于或等于年龄和性别特异性均值）以及5例接受了全甲状腺切除术的女性进行了研究。每位受试者在5分钟内接受每千克体重2毫克元素钙的静脉输注，以测试C细胞分泌储备。我们通过放射免疫分析法在全血浆和血浆的硅胶柱提取物中测量降钙素，后一种方法对单体降钙素具有大大提高的灵敏度和特异性。无论在全血浆还是提取物中测量，骨质疏松症患者的基础免疫反应性降钙素浓度均显著高于健康对照者（P<0.01）。通过钙刺激评估的降钙素分泌储备在骨质疏松症组中正常，但在甲状腺切除组中几乎不存在。我们得出结论，绝经后骨质疏松症与降钙素缺乏无关，也不是由降钙素缺乏引起的。相反，骨骼钙过度释放可能会刺激该疾病患者的降钙素分泌。
