摘要
目的研究牛磺酸对糖尿病大鼠坐骨神经结构、功能以及神经生长因子mRNA表达的影响。方法54只雄性Wistar大鼠随机分为模型组、牛磺酸组和正常对照组,每组各18只。大鼠于禁食12h后,一次性腹腔注射1%链脲佐菌素诱导制备糖尿病大鼠模型;72h后尾静脉采血测定血糖水平,>16.7mmol/L者纳入实验。模型制备后第8周末于光学显微镜和电子显微镜下观察坐骨神经形态改变。同时行逆转录聚合酶链反应半定量分析神经生长因子mRNA含量;化学比色法检测血清丙二醛含量;采用MS302多媒体生物信号系统分别记录模型制备后第4周、8周时大鼠坐骨神经运动神经传导速度。结果(1)与模型组相比,牛磺酸对链脲佐菌素诱导的糖尿病大鼠的体质量和血糖水平无明显改善(P>0.05)。(2)与正常对照组相比,模型组和牛磺酸组大鼠在注射链脲佐菌素后第8周血清丙二醛水平明显升高(均P<0.01),但牛磺酸组低于模型组(P<0.01)。(3)与正常对照组相比,模型组大鼠坐骨神经运动神经传导速度在制模后第4周、8周明显减慢(均P<0.01);同期牛磺酸组与模型组间差异亦有显著性意义(均P<0.05)。(4)病理观察显示,模型组和牛磺酸组大鼠在注射链脲佐菌素后第8周均表现为明显的损伤反应,但牛磺酸组病变程度较轻。(5)与正常对照组相比,注射链脲佐菌素后第8周模型组大鼠神经生长因子mRNA表达水平显著下降(P<0.01),牛磺酸组表达水平高于模型组(P<0.01)。结论牛磺酸对糖尿病周围神经病变的防治作用不是直接通过降低血糖水平,而可能是通过有效清除自由基,减轻脂质过氧化,上调神经生长因子mRNA表达而改善神经损伤实现的。
Objective To study the effects of taurine on structure, function and nerve growth factor （NGF） mRNA expression of sciatic nerve in diabetic rats. Methods The 54 male Wistar rats were randomly divided into taurine-treated group （n = 18）, modle group （n = 18） and normal control group （n = 18）. After 12 hours of fasting in both model and taurine-treated group, experimental diabetes were established by intraperitoneal injection of 1% streptozotoein （STZ）. Correspondingly the rats in normal control group received a same dose of intraperitoneal injection of citric acid buffer alone. Diabetes was defined as a nonfasting plasma glucose level greater than 16.7 mmol/L in tail vein blood 72 hours after STZ injection. On the succeeding induction by STZ, the diabetic model rats were enrolled in the study. At the end of the 8th weeks after establishing the models, various parameters were measured as follows： morphological study of sciatic nerve under light microscope and transmission electron microscope; evaluation of NGF mRNA level by reverse-transcriptase polymerase chain reaction （RT-RCR）; the serum malondialdehyde （MDA） level was analysed by ehromatometry, and the speed of nerve conduction was recorded on 4th and 8th week by using the MS302 style of media bio-signal system. Results 1） Compare with the modle group, taurine has no significant ameliorating in weight and blood glucose of the diabetic rats induced by streptozotoein （P〉 0.05）. 2） Compare with the normal control group, the rats in model group and taurine-treated group have a significant increase in serum MDA on the 8th week after injecting STZ （P〈0.01）, but the serum MDA level in taurine-treated group was lower than that of the model group （P〈 0.01）. 3） Compare with the normal control group, the sciatic nerve conduction velocity of the model group is significantly slow on the 4th and 8th week after successful induction by STZ （P〈 0.01）, and at the same time there was also a significant difference between the taurine-treated group and model group （P 〈 0.05）. 4） In pathological observation there were obvious injury reactions on the rats in both model group and taurine-treated group on the 8th week after STZ injection, but the reactions intaurine-treated group were weaker than that in model group. 5） To compare with the normal control group, the expression of NGF mRNA was significantly decreasing in modle group （P〈 0.01） but on the 8th week after STZ injection, and its level in taurine-treated group was higher than that in model group （P〈 0.01）. Conclusion The effects of taurine on prevention and threatment in diabetic peripheral neuropathy may be achieved by removing free radicals, reducing lipid peroxidation and up-regulation the expression of NGF mRNA, but not due to decrease blood glucose.
出处
《中国现代神经疾病杂志》
CAS
2006年第2期128-133,共6页
Chinese Journal of Contemporary Neurology and Neurosurgery
基金
湖南省卫生厅中医药重大研究项目(202002-3)
