硅橡胶植入对关节软骨Ⅰ、Ⅱ、Ⅲ型胶原合成的影响

Effect of Silicone Rubber Implantation on CollagenⅠ,Ⅱ,Ⅲ Expression of Articular Cartilage

目的 :观察植入硅橡胶对兔关节软骨细胞Ⅰ、Ⅱ、Ⅲ型胶原合成的影响。方法 :18只成年新西兰大白兔 ,每只动物右膝为实验组 ,在膝关节滑车处植入硅橡胶 ;左膝为对照组 ,膝关节滑车处造成关节软骨缺损后不植入硅橡胶。分别于术后 4周、2 4周和 4 8周取材 ,采用原位杂交的方法观察关节软骨细胞Ⅰ、Ⅱ、Ⅲ型前胶原mRNA的表达 ,同时运用免疫组织化学的方法观察关节软骨细胞Ⅰ、Ⅱ、Ⅲ型胶原蛋白的合成。结果 :实验组中关节软骨可见Ⅱ型前胶原mRNA和胶原蛋白的稳定表达。Ⅰ型前胶原mRNA从术后 4周起即有表达 ,且随时间延长而表达增加。但Ⅰ型胶原染色仅在 2 4周时方开始呈现阳性。Ⅲ型前胶原的mRNA则在各期均未探测到 ,但从 2 4周起Ⅲ型胶原染色呈阳性。对照组关节软骨在术后 4周时即可见到Ⅰ、Ⅱ、Ⅲ型前胶原mRNA和胶原蛋白同时表达 ,且对照组中Ⅰ、Ⅱ、Ⅲ型前胶原mRNA和胶原蛋白表达均呈减少趋势。结论 :(1)前胶原mRNA的表达早于胶原分泌。Ⅰ型前胶原mRNA表达在实验组中比对照组晚 ,而且实验组中Ⅰ型前胶原mRNA的表达时间较长 ,容易观察到阳性的表达信号 ,所以Ⅰ型前胶原mRNA可以成为早期骨关节炎 (OA)的分子标志物。 (2 )Ⅲ型前胶原mRNA由于表达时间可能较短 ,所以即使在实验组有Ⅲ型胶原蛋白分泌 ,但不易?

Objective To determine the effect of silicone rubber implantation on collagen Ⅰ, Ⅱ,Ⅲ systhesis of articular cartilage. Methods Eighteen matured New Zealand White rabbits underwent surgery on both knees. Full-thickness osteochondral defect was made on the trochlea zone. On the right knee, the defect was plugged tightly with hard silicone rubber as experimental group, while on the left knee the defect was left open as control. Rabbits were sacrificed at 4, 24 and 48 weeks respectively. The mRNA of procollagen Ⅰ, Ⅱ, Ⅲ in surrounding articular cartilage were investigated by in situ hybridization(ISH). The protein of collagen Ⅰ, Ⅱ,Ⅲ were investigated by immunohistochemical method. Results In experimental group, positive signals of procollagen Ⅱ mRNA and collagen type Ⅱ maintained steadily at 4, 24 and 48 weeks. Procollagen Ⅰ mRNA showed positive signals at 4 weeks after the surgery and increased with time passed by. The protein of collagen Ⅰ showed positive staining at 24 weeks after the surgery. No positive signals of procollagen Ⅲ mRNA were found at all time intervals, however, the protein of collagen Ⅲ showed positive staining at 24 and 48 weeks. In control group, positive signals of procollagen Ⅰ,Ⅱ, Ⅲ mRNA and collagen Ⅰ, Ⅱ, Ⅲ were found since 4 weeks after the surgery. All the three kinds of mRNA and proteins decreased from 4 to 48 weeks in control group. Conclusion 1. The expression of procollagen mRNA was earlier than the synthesis of collagen protein. The expression of procollagen Ⅰ mRNA was later than it in the control group, and the expression time was longer. It was easy to observe, so the procollagen Ⅰ mRNA could be a molecular marker for earlier osteoarthritis. 2. The expression time of procollagen Ⅲ mRNA might be very short, so even the expression of collagen Ⅲprotein could be found but the expression of procollagen Ⅲ mRNA might not be found. Therefor the procollagen Ⅲ mRNA could not be the proper marker for earlier osteoarthritis. 3. Silicone rubber implantation could delay the pathogenetic progression of osteoarthritis effectively.