降钙素基因相关肽和腺苷2A受体在偏头痛模型大鼠中的表达及作用机制

Expression and significance of calcitonin gene-related peptide and adenosine 2A receptor in migraine model rats

目的通过检测降钙素基因相关肽(calcitonin gene related peptide,CGRP)及腺苷2A受体(adenosine 2Areceptor,A2AR)蛋白在偏头痛模型大鼠三叉神经组织中的表达,探讨CGRP和A2AR在大鼠偏头痛发病机制中的作用。方法将30只雄性Sprague-Dawley(SD)大鼠随机分为对照组和模型组,每组15只。模型组采用每周1次皮下注射硝酸甘油法建立无先兆性偏头痛模型,共5周;对照组则用生理盐水皮下注射代替硝酸甘油。对两组大鼠进行行为学评分,而后采集两组大鼠颅底三叉神经节,采用免疫组化法检测三叉神经节中CGRP的表达;采用免疫荧光检测法观察三叉神经节中A2AR表达;采用westernblot法检测A2AR蛋白表达量。结果三叉神经节组织HE染色结果:模型组和对照组均显示神经元与神经纤维分布正常、无紊乱,解剖结构完整,无异常改变。三叉神经节中A2AR蛋白表达的Western-blot量及灰度值测定结果:模型组A2AR蛋白表达量及灰度值高于对照组。差异均有统计学意义(P<0.01)。三叉神经组织中A2AR表达蛋白免疫荧光测定结果及A2AR阳性神经元细胞数:模型组中A2AR在三叉神经各神经元中的免疫荧光的表达分布明显多于对照组模型组。模型组表达A2AR的阳性神经元细胞数高于对照组,差异有统计学意义(P<0.01)。三叉神经节CGRP免疫组化表达水平及OD值结果:模型组CGRP及OD值的表达水平明显高于对照组,差异有统计学意义(P<0.01)。结论模型大鼠偏头痛发作时,三叉神经组织无解剖结构上的改变,大鼠行为学改变与三叉神经功能异常有关。A2AR的激活或蛋白上调,CGRP的大量释放。A2AR、CGRP可能在偏头痛的发作中起重要作用。

Objective Through the detection of calcitonin gene related peptide（calcitonin gene related peptide,CGRP）and adenosine 2 Areceptor（adenosine 2 A,receptor,A2 AR）protein expression in the trigeminal nerve tissue of migraine model rats to investigate the role of CGRP and A2 AR in the pathogenesis of migraine in rats.Methods 30 male Sprague-Dawley（SD）rats were randomly divided into control group and model group,15 rats in each group.Migraine model without aura was established.The rats in the model group were subcutaneously injected with nitroglycerin,which was administered 1 times a week for 5 weeks.The control group was injected with saline instead of nitroglycerin.Behavioral scores were scored on two groups of rats.Then we collected two groups of rat skull base trigeminal ganglia.The expression of CGRP in the trigeminal ganglion was detected by immunohistochemistry,and the expression of A2 AR in the trigeminal ganglion was detected by immunofluorescence method.The expression ofA2 AR protein was detected by Western blot method.Results The model group and the control group showed normal distribution of neurons and nerve fibers,no disturbance,complete anatomical structure,and no abnormal change.The expression of A2 AR protein and gray level in model group were higher than those in control group（P〈0.01）.In the model group,the expression of A2 AR in the trigeminal nerve neurons was significantly more than that in the control group.The number of positive neurons in the model group expressing A2 AR was higher than that in the control group（P〈0.01）.The expression level of CGRP in the model group and was significantly higher than the control group（P〈0.01）.Conclusion There were no anatomical changes in the trigeminal nerve tissue during the migraine attack in the model rats.The behavioral changes of rats are related to the dysfunction of trigeminal nerve.Expression of A2 AR activation or protein upregulation,and mass release of CGRP.A2 AR and CGRP may play an important role in the pathogenesis of migraine.