目的：发育性髋脱位（developmental dislocation of the hip, DDH）的病因目前不明，但其与髋关节松弛密切相关。该研究通过比较DDH患儿与正常儿童关节囊中Ⅰ，Ⅲ型胶原在mRNA及蛋白水平的表达差异, 以探索DDH患儿髋关节松弛的原因。方法：选取性别相同年龄相近的9对发育性髋脱位患者及正常儿童配对比较。采用半定量RT-PCR及Western-Blot法检测COL1a1 COL3a1在mRNA及蛋白水平的表达。图像分析软件进行量化分析,并经统计学处理。结果：COL1a1在DDH组mRNA及蛋白水平表达均较正常对照组降低(P<0.01)；COL3a1在DDH组mRNA水平表达较正常对照组降低(P<0.01)，其蛋白水平表达与正常对照组无显著差异(P>0.05)。结论： DDH患儿关节囊中 Ⅰ 型胶原在mRNA及蛋白水平表达较正常同性同龄儿降低，可能是导致DDH患儿髋关节松弛的原因。DDH患儿髋关节松弛可能与 Ⅲ 型胶原含量无关。

ObjectiveThe etiology of developmental dislocation of the hip (DDH) remains uncertain, but some research has shown that this disorder is closely related to hip joint laxity. This study examined the expression of collagens type I and III mRNA and protein in the hip capsule of children with DDH in order to investigate the roles of collagens type I and III in hip joint laxity. MethodsNine children with DDH and nine age and gender-matched normal children (control group) were enrolled. Semiquantitative RT-PCR method was used to detect mRNA expression of COL1a1 and COL3a1 in the hip capsule. Western-Blot method was used to detect protein expression of COL1a1 and COL3a1 in the hip capsule. The quantitative analysis of the COL1a1 and COL3a1 was performed by professional image software and the results were analyzed with standard statistical methods.ResultsmRNA and protein expression of COL1a1 in the DDH group was significantly lower than that in the control group (P<0.01). Compared with the control group, COL1a3 mRNA expression in the DDH group decreased significantly (P<0.01), but COL1a3 protein expression was not significantly different.ConclusionsThe decreased collagen I mRNA and protein expression in the hip capsule might contribute to hip joint laxity in children with DDH. Collagen type III may not be associated with hip joint laxity in DDH.