胰岛素样生长因子I受体在宫同内发育心缓胎鼠中的表达研究

目的 探讨宫内发育迟缓（IUGR）时胰岛素样生长因子I受体（IGFD－1R）表达的变化及其在组织和细胞中的定位。方法 将21只SD孕鼠随机分为实验组12只和对照组9只。钳夹实验组孕鼠双侧子宫动、静脉20分钟，建立宫内发育迟缓动物模型。对照组仅作开腹和关腹术。两组均于孕22天剖宫取出胎鼠，采用免疫组化法观察孕晚期胎鼠肝脏和肺组织中IGF－1R的表达。结果 实验组胎鼠的体重、身长及胎盘、肝、肺组织重量按对照组明显降低（P＜0．05）；实验组胎鼠肝脏IGF－1R表达面积比较对照组明显增加，平均灰度明显降低（P＜0．01）；实验组胎鼠肺组织IGF－1R表达面积也比较对照组明显增加（P＜0．05），但平均灰度则无显著性差异（P＞0．05）。结论 宫内发育迟缓时IGF－1R在肝脏和肺组织的表达增加，可能是机体对IGF－1降低的代偿机制。

Studies on insulin-like growth factor I receptor in fetal rats with intrauterine growth retardation]

OBJECTIVE: This study was conducted to detect the localization of the insulin-like growth factor I receptor (IGF-I R) in the cells and tissues in the rats with intrauterine growth retardation (IUGR) and normal growth rats. METHODS: 21 pregnant rats were randomly divided into the experimental group (IUGR) (n = 12) and the control group (n = 9). Animal models for IUGR were established by clamping the uterine vasculature of pregnant rats for 20 minutes on day 14 of gestation. The control group rats were subjected to Sham-operation. On day 22 of gestation, fetal rats were delivered by cesarean section. Immunohistochemical assay was performed to detect the IGF-I R expression on liver and lung using specific polyclonal antibodies to rat IGF-I R. RESULTS: In the experimental group, the IUGR rats' body weight, height, and the weight of their liver, lung and the placenta were significantly lower than those in the control group. In the IUGR rats' liver, the area ratio of IGF-I R was increased and the average gray level was decreased, compared with those in the control group. In the IUGR rats' lung, the area ratio of IGF-I R was increased, compared with that in the control group, but no difference of average gray level was observed between the two groups. CONCLUSION: The increased expression of IGF-I R in rats with IUGR, may be due to the decrease of IGF-I and the compensative mechanism of the body.