睫状神经营养因子和脑源性神经营养因子对动眼神经切断后猫动眼神经核神经丝蛋白表达的影响

Effect of ciliary neuronotrophic factor and brain-derived neurotrophic factor on the expression of neurofilament protein in oculomotor nucleus of cats after oculomotor nerve transection

目的:观察外源性睫状神经营养因子和脑源性神经营养因子对动眼神经切断后猫动眼神经核神经丝蛋白表达的影响。方法:实验于2004-06/2005-06在中南大学湘雅医学院人体解剖学应用解剖研究室完成。选用健康成年猫30只,建立猫动眼神经切断后硅胶管再生室模型,将建模成功20只随机分为4组,分别为脑源性神经营养因子组、睫状神经营养因子组、脑源性神经营养因子+睫状神经营养因子组和生理盐水组,每组5只。术后再生室内分别给予睫状神经营养因子、脑源性神经营养因子、脑源性神经营养因子+睫状神经营养因子和生理盐水各15μL(因子浓度为33mg/L),存活12周后用免疫组织化学方法检测各组动物动眼神经核内神经丝蛋白免疫反应阳性细胞数及阳性细胞灰度值的变化。结果:猫30只,造模失败10只,最终进入结果分析20只。①各组动物对照侧动眼神经核内神经丝蛋白免疫反应阳性神经元数目和灰度值差异无显著性(P>0.05)。②生理盐水组手术侧动眼神经核内神经丝蛋白免疫反应阳性神经元数目低于对照侧,差别具有显著性(P<0.05)。各营养因子组术侧动眼神经核的神经丝蛋白免疫反应阳性神经元数目和免疫染色强度均明显高于生理盐水组(P<0.05);③在各营养因子组中,脑源性神经营养因子+睫状神经营养因子组明显高于脑源性神经营养因子组和睫状神经营养因子组(P<0.05),脑源性神经营养因子组与睫状神经营养因子组之间无明显差别。脑源性神经营养因子+睫状神经营养因子组与同组动物未手术侧相比差别均无显著性(P>0.05),而脑源性神经营养因子组和睫状神经营养因子组与同组动物未手术侧相比差别均有显著性(P<0.05)。结论:外源性睫状神经营养因子和脑源性神经营养因子均可上调动眼神经切断后猫动眼神经核的神经丝蛋白表达,联合应用具有协同作用。

AIM： To observe the effect of exogenous ciliary neuronotrophic factor （CNTF） and brain-derived neurotrophic factor （BDNF） on the expression of neurofilament protein in oculomotor nucleus of cats after oculomotor nerve transection. METHODS： The experiments were finished in the Applied Anatomy Lab of the D.epartment of Anatomy and Neurobiology, Xiangya School of Medicine, Central South University between June 2004 and June 2005. Thirty healthy adult cats were used. The oculomotor nerves were transected and the silicon tube nerve regeneration chamber models were set up. Twenty models were successfully established, and then they were randomly divided into 4 groups with 5 cats in each： CNTF group, BDNF group, BDNF＋CNTF group and normal saline group, and the cats were injected with 15μL exogenous CNTF, BDNF, BDNF＋CNTF （concentration： 33 mg/L） or 15 μL normal saline into the silicon tube nerve regeneration chambers after the surgery respectively. After survived for 12 weeks, the changes of neurofilament protein immunepositive neurons were detected by immunohistochemistry and gray scale in oculomotor nucleus were analyzed by image analysis system. RESULTS： Of the 30 cats, 10 failed in the model establishment, and finally 20 were involved in the analysis of results. ①The number of neurofilament protein immune-positive neurons and gray scale in contralateral oculomotor nucleus in all groups had no significant differences （P 〉 0.05）.② In the normal saline group, the neurofilament protein immune-positive neurons in the ipsilateral oculomotor nucleus were significantly lower than those in the contralateral oculomotor nucleus（P 〈 0.05）. The neurofilament protein immune-positive neurons and gray scale in ipsilateral oculomotor nucleus in all neurotrophic groups were significantly increased compared with normal saline group （P 〈 0.05）. In the neurotrophic groups, the neurofilament protein immune-pesitive neurons and gray scale in the BDNF＋CNTF group were significantly higher than in the BDNF group and CNTF group （P 〈 0.05）. There was no significant difference between the BDNF group and CNTF group. In the BDNF＋CNTF group, the neurofilament protein immune-pesitive neurons and gray scale in ipsilateral oculomotor nucleus had no significant difference as compared with those in the contralateral oculomotor nucleus （P 〉 0.05）. In the BDNFgroup or CNTF group, the neurofilament protein immune-positive neurons and gray scale in ipsilateral oculomotor nucleus had significant difference as Compared with those in the contralateral oculomotor nucleus （P 〈 0.05）. CONCLUSION： Both exogenous CNTF and BDNF can Upregnlate the expression of neurofilament protein in oculomotor nucleus of cats after oculomotor nerve transection, and the combined use of CNTF and BDNF has synergistic effect.