有生长追赶SGA大鼠促生长素轴的改变  

Changes of somatotropin axis in catch-up growth rats born small for gestational age

作　　者：邓红珠[1,2] 邓洪[3] 马华梅[2] 沈振宇[2] 杜敏联[2] 

机构地区：[1]中山大学附属第三医院儿科,广东广州510630 [2]中山大学附属第一医院儿科,广东广州510089 [3]中山大学附属第三医院感染科,广东广州510630

出　　处：《中国病理生理杂志》2011年第7期1360-1365,共6页Chinese Journal of Pathophysiology

基　　金：广东省自然科学基金资助项目(No.9151008901000079)

摘　　要：目的:研究青春前期有生长追赶的小于胎龄(SGA)大鼠促生长素轴的改变,探讨SGA个体生长追赶可能的发生机制。方法:应用孕鼠全程饮食限制法制备SGA大鼠模型,测定4周龄子鼠尿生长激素(GH)排泄率、血胰岛素样生长因子-1(IGF-1)浓度、肝脏组织IGF-1 mRNA表达和胫骨生长板IGF-1、胰岛素样生长因子-1受体(IGF-1R)表达。结果:有生长追赶SGA(CUG-SGA)大鼠尿GH水平显著高于无生长追赶SGA(NCUG-SGA)和适于胎龄(AGA)大鼠(P<0.05,P<0.01);血IGF-1水平CUG-SGA显著高于NCUG-SGA组(P<0.01),与AGA组无显著差异。CUG-SGA组肝脏IGF-1 mRNA表达较NCUG-SGA显著增高(P<0.01),与AGA相比无显著差异。胫骨生长板形态学的改变:SGA鼠生长板增殖区每柱细胞数较少,各期软骨细胞排列不规则。NCUG-SGA组生长板总厚度、各区厚度均较CUG-SGA和AGA组显著降低;CUG-SGA组生长板厚度与AGA组比较无显著差异,但肥大区厚度较NCUG-SGA和AGA组显著增高(P<0.01,P<0.05)。CUG-SGA组胫骨生长板软骨细胞IGF-1表达较NCUG-SGA显著增多(P<0.01),与AGA组比较无显著差异;3组间IGF-1R表达无显著差异(P>0.05)。结论:SGA大鼠无论生后追赶与否均存在GH/IGF-1轴抵抗,其生后不同的线性生长追赶方式可部分归咎于其抵抗程度。AIM： To evaluate the changes of somatotropin axis in pre-pubertal rats with catch-up growth born small for gestational age（CUG-SGA）.METHODS： The SGA rat model was prepared by diet restriction in pregnant rats.Growth hormone（GH） excretion in 24-h urine,serum level of insulin-like growth factor-1（IGF-1）,the expression of IGF-l and insulin-like growth factor-1 receptor（IGF-1R） in the tibial growth plate and the mRNA expression of IGF-1 in liver were measured in infant rats at the end of week 4.RESULTS： The level of 24-h urinary GH excretion in CUG-SGA group were significantly higher than that in the rats of non-catch-up growth born small for gestational age（NCUG-SGA） group and appropriate for gestational age（AGA） group（both P0.01）.The serum level of IGF-1 and the mRNA expression of IGF-1 in liver in CUG-SGA group were similar to those in AGA group,but significantly higher than those in NCUG-SGA group.The thickness of the tibial growth plate in NCUG-SGA group was significantly lower than that in CUG-SGA group and AGA group.No difference of the growth plate thickness between CUG-SGA group and AGA group was observed,but the thickness of hypertrophy zone of the growth plate in CUG-SGA group were significantly higher than that in NCUG-SGA group and AGA group（both P0.01）.The expression of IGF-1 in the growth plate in CUG-SGA group was similar to that in AGA group but significantly higher than that in NCUG-SGA group（P0.01）.No difference of the IGF-1R expression in the growth plate among these 3 groups was found（P0.05）.CONCLUSION： GH/IGF-1 resistance exists in SGA rats with and without catch-up growth.

关 键 词：生长追赶 小于胎龄儿 促生长素轴 

分 类 号：R363[医药卫生—病理学]