Kotowicz M A, Klee G G, Kao P C, O'Fallon W M, Hodgson S F, Cedel S L, Eriksen E F, Gonchoroff D G, Judd H L, Riggs B L
Endocrine Research Unit, Mayo Clinic, Rochester, Minnesota 55905.
Osteoporos Int. 1990 Oct;1(1):14-22. doi: 10.1007/BF01880411.
To define the role of parathyroid gland function in the pathophysiology of bone loss in type I (postmenopausal) osteoporosis, we measured serum intact parathyroid hormone (PTH) concentration by immunoradiometric assay (IRMA) and by multisite immunochemiluminometric assay (ICMA) in 63 postmenopausal osteoporotic women (PMOp) with vertebral compression fractures and in 75 age-comparable postmenopausal normal women (PMNl). Also, tetracycline-based histomorphometric indices in cancellous bone were assessed in iliac biopsy samples from 61 PMOp and 28 PMNl women. Serum PTH concentrations by IRMA were similar in PMOp and PMNl (medians, 3.92 and 3.77 pmol/l; NS) but were significantly lower in PMOp by the more sensitive ICMA (medians, 2.82 and 3.14 pmol/l; P less than 0.01). By multiple linear regression analysis, serum PTH was directly related (P less than 0.001) to activation frequency, bone resorption rate, bone formation rate, and the calculated rate of bone loss. For each unit (pmol/l) increase in serum PTH by ICMA, activation frequency increased by 1.3%/year more (P = 0.01), bone resorption rate increased by 3.9%/year more (P = 0.003), and the rate of cancellous bone loss was 2.8% greater (P = 0.0003) in the PMOp women compared with the PMNl women. Concentrations of serum estradiol, but not serum estrone, had a weak opposing effect to PTH, especially for bone formation rate. These data suggest that in PMOp the bone has increased sensitivity to the biologic effects of PTH. This may represent one of the fundamental pathophysiologic defects in PMOp and, in the setting of estrogen deficiency, may explain, in part, their greater rate of bone loss.
为了明确甲状旁腺功能在I型（绝经后）骨质疏松症骨质流失病理生理过程中的作用，我们采用免疫放射分析法（IRMA）和多部位免疫化学发光分析法（ICMA），对63例患有椎体压缩性骨折的绝经后骨质疏松症女性（PMOp）和75例年龄相仿的绝经后正常女性（PMNl）的血清完整甲状旁腺激素（PTH）浓度进行了测定。此外，还对61例PMOp女性和28例PMNl女性髂骨活检样本中的松质骨基于四环素的组织形态计量学指标进行了评估。通过IRMA测定的PMOp和PMNl血清PTH浓度相似（中位数分别为3.92和3.77 pmol/L；无显著性差异），但采用更敏感的ICMA测定时，PMOp的血清PTH浓度显著降低（中位数分别为2.82和3.14 pmol/L；P<0.01）。通过多元线性回归分析，血清PTH与激活频率、骨吸收速率、骨形成速率以及计算得出的骨质流失速率直接相关（P<0.001）。ICMA测定的血清PTH每升高1个单位（pmol/L），激活频率每年增加1.3%以上（P=0.01），骨吸收速率每年增加3.9%以上（P=0.003），与PMNl女性相比，PMOp女性的松质骨流失速率高2.8%（P=0.0003）。血清雌二醇浓度而非血清雌酮浓度对PTH有微弱的拮抗作用，尤其是对骨形成速率。这些数据表明，在PMOp中，骨骼对PTH的生物学效应敏感性增加。这可能代表了PMOp基本的病理生理缺陷之一，并且在雌激素缺乏的情况下，可能部分解释了她们更高的骨质流失速率。
