生长激素对大鼠胫骨生长板软骨细胞胶原Ⅱ表达的影响

Effect of growth hormone on the expression of collagen Ⅱ of cultured growth plate chondrocytes of rats

目的探讨生长激素（growth hormone，GH）对离体培养的大鼠胫骨生长板的软骨细胞Ⅱ型胶原（collagenⅡ，colⅡ）表达的影响。方法采用两步酶消化法分离培养5～8只三周龄大鼠生长板的软骨细胞，用RT—PCR和免疫组化的方法分别检测不同浓度GH对软骨细胞Ⅱ型胶原mRNA和蛋白的表达。结果GH能促进软骨细胞ColⅡ的表达并呈浓度依赖性，GH在10～500ng/ml之间能促进ColⅡ的表达，与对照组比较差异均有统计学意义（P〈0．05），并且以100ng／ml时表达最强，随着GH浓度的加大，其促ColⅡ表达的效应逐渐减弱，1000ng／ml与对照组比较无差异（P〉0．05）。结论GH通过促进软骨细胞ColⅡ的表达能维持软骨细胞的表型，GH在使用过程中不会导致骨龄的增加。

Objective To observe the effect of growth hormone on the expression of collagen Ⅱ of cultured growth plate chondroeytes of rats. Methods Primary chondrocytes from tibial growth plate of 5 - 8 rats by trypsin-collagenase digestion were cultured in monolayer. RT-PCR and immunocytochemistry were performed to investigate the expression of collagen Ⅱ at the mRNA and protein level, respectively with different concentrations of GH. Results GHenhances the expression of collagen Ⅱ of chondrocytes in vitro in a concentration-dependent fashion. The expression of collagen Ⅱ was obviously between the GH concentration of 10 ng/ml and 500 ng/ml （P 〈 0. 05 ）, maximally at the concentration of 100 ng/ml, and decreased again after higher concentration of GH. There was no significant difference between 1000 ng/ml group and control group （P 〉 0. 05 ）. Conclusion GH can maintain the phenotype of chondrocytes by enhancing the expression of collagen Ⅱ and it will not increase the bone age during clinical practice.