宫内发育迟缓大鼠血清胰岛素样生长因子Ⅰ、Ⅱ、BP3的变化及L-精氨酸的保护作用

Effect of L-arginine on the alterations of serum insulin-like growth factor and insulin-like growth factor binding protein 3 in intrauterine growth retardation rats.

目的通过L-精氨酸孕期干预后大鼠血清胰岛素样生长因子-Ⅰ、Ⅱ及结合蛋白3水平的变化,探讨L-精氨酸的保护作用及其机制。方法采用被动吸烟法造大鼠IUGR模型,孕鼠随机分为4组:对照组、模型组、L-精氨酸小剂量和大剂量防治组,每组9只。孕21d剖宫取胎,测量胎鼠体重。应用酶联免疫吸附法检测各组大鼠血清IGF-Ⅰ、IGF-Ⅱ及IG-FBP-3水平。结果对照组、模型组与小、大剂量L-精氨酸防治组IUGR发生率分别为3.92%,54.95%,5.55%和9.09%。模型组大鼠血清IGF-Ⅰ、IGF-Ⅱ水平较对照组明显降低(P<0.01),小剂量和大剂量L-精氨酸防治组与模型组相比,IGF-Ⅰ、IGF-Ⅱ水平明显增高(P<0.01)。模型组大鼠血清IGFBP-3水平较对照组明显增高(P<0.01),小剂量和大剂量L-精氨酸防治组与模型组相比,IGFBP-3水平明显降低(P<0.01),与对照组亦有明显差异(P<0.01)。结论L-精氨酸可增高被动吸烟致宫内发育迟缓大鼠血清胰岛素样生长因子-Ⅰ、Ⅱ的水平,降低胰岛素样生长因子结合蛋白3的水平,从而促进胎鼠发育,防治IUGR的发生。

Objective： This study aimed to explore the effect and its mechanism of L -arginine on IUGR rats by the alterations of serum insulin - like growth factor - Ⅰ （ IGF - Ⅰ） ,insulin - like growth factor -Ⅱ （ IGF -Ⅱ ） and insulin - like growth factor binding protein 3 after different doses of L - arginine were administered. Methods： Thirty - six rats were divided into four groups： Control, Model, Low dose（ lOOmg/kg L - arginine） and High dose （200mg/kg L - arginine） （n = 9 each）. IUGR was induced by passive smoking in rats from the last three groups. L - arginine was administered for the last two groups between day 8 and day 20 of gestation. On day 21 of gestation, the fetal rats were delivered by cesarean section. The body weight of fetal rats were measured. The levels of IGF - Ⅰ , IGF - Ⅱ and IGFBP - 3 in the serum of pregnancy rats were measured by enzyme - linked immunoadsordent assay （ELISA）. Results： The incidence of IUGR in control, model, low dose and high dose group was 3. 92% , 54. 95%, 5.55% and 9. 09% respectively. The incidence of IUGR in Model group was increased significantly compared with that of control group（ P 〈 0. 01 ）, and the IUGR incidence of L - arginine treated groups were decreased compared with model group（ P 〈 0. 01 ）. The serum IGF - Ⅰ and IGF - Ⅱ levels of pregnancy rats in model group were significantly lower than those of control group（ P 〈0. 01 ）. The levels of IGF-Ⅰ and IGF- Ⅱ in L- arginine treated groups were increased significantly than those of model group（ P 〈0. 01 ）. The serum IGFBP- 3 levels of pregnancy rats in model group were significantly higher than those of control group（ P 〈 0. 01 ）. The levels of IGFBP -3 in L - arginine treated groups were decreased significantly than those of model group （ P 〈 0. 01 ）and there were statistical difference between L- arginine treated groups and control group（ P 〈 0. 01 ）. Conclusion： L- arginine can increase the levels of IGF - Ⅰ and IGF - Ⅱ in the serum of IUGR rats by passive smoking, decrease the levels of IGFBP - 3, improve the development of fetal rats and decrease the incidence of IUGR.