绝经后骨质疏松症病人Ⅰ型胶原的变化

THE CHANGES OF TYPE Ⅰ COLLAGEN IN POSTMENOPAUSAL OSTEOPOROSIS

目的 研究Ⅰ型胶原合成及代谢在绝经后骨质疏松症发病中的作用。 方法 以绝经后骨质疏松性骨折病人股骨头置换术弃去的股骨头为样本 ;采用苦味酸天狼星红 偏振光及Ⅰ型胶原和基质金属蛋白酶 1(MMP 1)抗体免疫组织化学染色 ,从蛋白水平观察骨中Ⅰ型胶原的分布和量的变化 ;地高辛标记的Ⅰ型胶原和MMP 1cDNA基因探针进行原位杂交 ,从mRNA水平观察Ⅰ型胶原和MMP 1的分布和量的变化 ;从骨中提取Ⅰ型胶原测定肽链的羟基化水平 ,观察Ⅰ型胶原羟基化程度的改变。 结果 绝经后骨质疏松性骨折病人胶原含量降低 ,Ⅰ型胶原蛋白纤维变细、断裂 ,结构紊乱。而细胞内Ⅰ型胶原和MMP 1mRNA以及MMP 1蛋白水平均升高。Ⅰ型胶原蛋白赖氨酸羟基化程度升高而脯氨酸羟基化程度不变。 结论 Ⅰ型胶原合成及代谢在质和量上的改变在绝经后骨质疏松症发病中起重要作用。

Objective To analyze synthesis and metabolic changes of bone type Ⅰ collagen in the pathogenesy of postmenopausal osteoporosis. Methods Femoral heads of patients were obtained during hip replacement surgery with osteoporotic fracture,and were observed by in situ hybridization with dig-labeling cDNA and by immunohistochemistry with both antibodies of type Ⅰ collagen and MMP-1,and by picrosirius-polarization.The detection of hydroxyproline method was used. Results A decrease in the level of bone collagen was detected in osteoporosis patients,the type Ⅰ collagen fibrils in diameter thinned, were broke,and its structure irregular;the mRNA expression level of type Ⅰ collagen and MMP-1 increased in osteoblasts.The hydroxylation level of lysine elevated.Conclusion The changes of type Ⅰ collagen synthesis and metabolism,both in quality and quantity,play an important role in the pathogenesy of postmenopausal osteoporosis.