去卵巢大鼠腰椎松质骨中胰岛素样生长因子1的表达

Expression of insulin-like growth factor in the cancellous bone of lumbar spine in ovariectomized rats

目的观察去卵巢大鼠腰椎松质骨中胰岛素样生长因子1蛋白质表达与细胞定位及骨代谢水平变化。方法①实验于2000-10/2002-01在解放军第四军医大学西京医院骨科研究所实验室完成。采用4月龄SD雌性大鼠20只,随机分为2组卵巢切除组10只和假手术组10只。②麻醉后,去卵巢组大鼠切除双侧卵巢,假手术组仅行开腹术。③16周后取大鼠腰椎,采用免疫组织化学方法观察腰椎松质骨中胰岛素样生长因子1的表达。用M550型计算机全自动图像分析仪对胰岛素样生长因子1的表达进行分析。采用全自动生化分析仪测定大鼠血清钙、磷、碱性磷酸酶水平。④组间计量资料差异性比较采用方差分析和t检验。结果大鼠20只均进入结果分析。①免疫组化染色显示,椎体松质骨中胰岛素样生长因子1主要分布在骨小梁周围成骨细胞、骨髓未分化细胞及骨小梁基质中。②图像分析结果显示,去卵巢组大鼠椎体松质骨胰岛素样生长因子1染色阳性细胞灰度值明显大于假手术组(P<0.05)。③去卵巢组大鼠术后16周血清钙和碱性磷酸酶水平明显高于对照组(P<0.01,0.05),血清磷水平与对照组接近。结论①去卵巢大鼠骨组织形态及骨代谢水平表现为高转换性骨代谢特征。②去卵巢后骨转换过程中胰岛素样生长因子1可能是偶联成骨细胞和破骨细胞的重要细胞因子。

AIM： To observe the expression and cellular localization of insulin-like growth factor-1 in the cancellous bone of lumbar spine in ovarieetomized rats, and detect the level of bone metabolism. METHODS： （1） The experiment was completed in the key laboratory of the Institute of Orthopaedics, Xijing Hospital of the Fourth Military Medical University of Chinese PLA from October 2000 to January 2002. Twenty 4-month-old female SD rats were randomly divided into two group.s： ovariectomized group （n=10） and sham-operated group （n=10）. （2） After anesthesia, rats in the ovarieetomized group were treated with bilateral ovariectomy, and those in the sham-operated group were only given laparotomy. （3） After 16 weeks, the lumbar spines of the rats were removed to ob- serve the expression of insulin-like growth factor-1 in the cancellous bone of lumbar spine of rats in both group with immunohistoehemistry. The expression of insulin-like growth factor-1 was analyzed with the M550 computerized automatic image analyzing system. The levels of serum calcium, phosphorus and alkaline phosphatase were detected with automatic biochemistry analyzer. （4） The analysis of variance and t test were applied in comparing the intergroup difference of measurement data. RESULTS： All the 20 rats were involved in the analysis of results. （1） The immunohistoehemical staining showed that the insulin-like growth factor-1 in the cancellous bone of lumbar spine mainly distributed in the osteoblasts around bone trabeeula, bone marrow undifferentiated cells and stroma of bone trabecula. （2） The results of image analysis indicated that the positive gray value of insulin-like growth factor-1 staining in the cancellous bone of lumbar spine was obviously larger in the ovariectomized group than in the sham-operated group （P 〈 0.05）. （3） After 16 weeks, levels of serum calcium and alkaline phosphatase in the ovariectomized group were obviously higher than those in the sham-operated group （P 〈 0.01, 0.05）, and the level of serum phosphorus was close to that in the sham-operated group. CONCLUSION： （1） The manifestations of bone tissue form and bone metabolism level in ovariectomizecI rats are the characteristics of high turnover bone metabolism. （2） Insulin-like growth factor-1 maybe play an important role in coupling to steoblasts and osteoclasts during bone transition in overiectomized rats.