THE EFFECT OF PREGNANCY,PARTURITION AND LACTATION ON BONE MINERAL METABOLISM IN HEALTHY WOMEN

(1)为了重新评估I型胶原蛋白血清吡啶啉交联羧基末端末端肽（ICTP）的临床应用价值，我们对76名日本绝经后健康女性、33名接受激素替代治疗的女性和43名未接受激素替代治疗的女性进行了为期6个月的研究，以评估其作为生化标志物的性能。在入组及6个月后测定腰椎（L2-L4）骨密度（BMD）、血清ICTP、I型前胶原羧基末端前肽（PICP）等常规血清生化指标。在测量的生物标志物中，ICTP变化百分比与BMD变化百分比的相关性最高（P<0.0001）。我们得出结论，血清ICTP是绝经后人群中一个敏感和有用的骨重新选择标志物，它与骨密度的变化密切相关。(2)通过纵向研究，探讨了产后人体骨代谢的变化及哺乳对其的影响。研究对象分为两组：13名产后3个月内停止母乳喂养的妇女（短期组）和14名产后6个月以上继续母乳喂养的妇女（长期组）。产前至产后3个月，两组血清PICP和ICTP值及其变化基本相同。PICP维持在恒定且显著高于控制值。ICTP在产后5 d明显升高，此后逐渐降低。产后9个月，短期组PICP和ICTP降至控制值。产后3个月时两组腰椎骨密度均有明显下降，短期组恢复到产后水平，而长期组在产后9个月时没有恢复到产后水平。总之，分娩和哺乳都会刺激骨吸收，导致产后腰椎骨密度下降。少

(1) To reassess the clinical utility of serum pyridinoline cross-linked carboxy terminal telopeptide of type I collagen (ICTP), a promising but controversial indicator of bone resorption, we evaluated its performance as a biochemical marker in a 6-month study of a strictly selected population of 76 Japanese postmenopausal and healthy women, 33 recipients of hormone replacement therapy and 43 non-recipients. We measured bone mineral density (BMD) of the lumbar spine (L2-L4), and serum ICTP,carboxyterminal propeptide of type I procollagen (PICP) and other conventional serum biochemical markers at the entry and 6 months later. Among the biomarkers measured, the percent change in ICTP correlated with that in BMD to the highest degree (P<0.0001). We concluded that serum ICTP is a sensitive and useful bone resoption marker in the postmenopausal population, which strongly correlates with the change in BMD.(2) A longitudinal study was performed to investigate postpartum changes in human bone m … More etabolism and the effects of lactation on them. The subjects consisted of two groups : 13 women who stopped breast-feeding within 3 months postpartum (short-term group) and 14 women who continued breast-feeding for more than 6 months postpartum (long-term group). Between prepartum and 3 months postpartum, the values and variations of serum PICP and ICTP were essentially the same in both groups. PICP was maintained at a constant and significantly higher level than the control value. In contrast, ICTP had increased markedly at 5 days postpartum, gradually decreasing thereafter. At 9 months postpartum, PICP and ICTP decreased to the control values in the short-term group. The postpartum time course of lumbar BMD showed a significant decrease in both groups at 3 months at 3 months postpartum and a recovery to the puerperal level in the short-term group but not in the long-term group at 9 months postpartum. In conclusion, bone resorption is stimulated by parturition as well as lactation resuting in postpartum loss of lumbar BMD. Less