左旋精氨酸对宫内发育迟缓胎鼠脑组织中NO、MDA和SOD的影响

目的了解左旋精氨酸对被动吸烟所致大鼠宫内发育迟缓及胎鼠脑发育的影响,通过其与NO、MDA和SOD的关系探讨其作用机制。方法利用被动吸烟法建立大鼠IUGR模型,孕鼠随机分为5组:对照组、模型组、低剂量左旋精氨酸组、中剂量左旋精氨酸组、高剂量左旋精氨酸组。孕21天剖宫取胎,观察胎仔体重、脑重、肝重;检测胎鼠脑组织中NO含量及MDA、SOD活性。结果与对照组比较,模型组胎仔体重、脑重、肝重均明显降低(P<0.01),胎鼠脑组织NO含量升高,MDA水平升高,SOD活性降低(P<0.01)。低剂量及中剂量左旋精氨酸组与模型组相比,胎仔体重、脑重、肝重各项指标均有所改善,NO含量降低,MDA水平降低,SOD活性增高(P<0.01),但高剂量左旋精氨酸组与模型组比较差异无显著性(P>0.05)。结论孕中期应用一定剂量左旋精氨酸可有效防治被动吸烟孕鼠IUGR的发生并对胎仔脑发育有显著促进与保护作用,其作用与机体的氧化与抗氧化平衡失调有关。

Effect of L-arginine on brains of IUGR fetal rats and levels of NO, MDA and SOD

Objective] To explore the effects of L-arginine on the brains of fetal rats with IUGR and the relationship with the levels of NO, MDA and SOD. Methods] After establishment of IUGR model with passive smoking, 45 rats were divided into 5 groups: control group, IUGR group, low dose of L-arginine (100 mg/kg) treated group, middle dose of L-arginine (200 mg/kg) treated group and high dose of L-arginine (400 mg/kg) treated group. On day 21 of gestation, the body weight, brain weight and liver weight of fetal rats were examined. The levels of NO, MDA and SOD activity in the brains of fetal rats were measured. Results] The average body weight, brain weight and liver weight of fetal rats of IUGR group were significantly lower than those of control group. The levels of NO and MDA in the brains of fetal rats were increased significantly, but the activity of SOD in the brains of fetal rats were decreased. All of these changes were improved in low and middle doses of L-arginine treated groups. No statistical difference was observed between high dose of L-arginine treated group and IUGR group. Conclusions] L-arginine can decrease the incidence of IUGR in rats of passive smoking and improve the development of the brains of fetal rats. The effect of L-arginine has some relationship with the unbalance between oxidate and antioxidate system.