大鼠交感节后神经元间钙调蛋白的差异性表达及其意义

Differential expression of calmoduUn in sympathetic postgangUonlc neurons and implication

目的观察大鼠不同节段交感节后神经元的钙调蛋白（CaM）的表达，探讨其与交感神经元电生理特征的关系。方法SD大鼠，采集交感神经链中的颈上神经节，颈胸神经节及腹腔神经节，采用逆转录-聚合酶链反应（RT-PCR）和免疫组织化学在mRNA和蛋白质水平分别观察并比较神经元钙调蛋白的表达。结果钙调蛋白在所选取的3个节段神经元中均有表达，颈上神经节组、颈胸神经节组及腹腔神经节组在mRNA水平的相对表达强度比值分别为1．19150±0．05009、1．18270±0．05393、1．03090±O．06624，在蛋白质水平的相对表达强度分别为63．38860±3．30938、61．43570±2．87909、48．77490±3．08877。其表达水平在颈上和颈胸神经节之间差异无统计学意义（q=0．6631、3．5366，P〉0．05），颈上和颈胸神经节的表达均明显高于腹腔神经节（q=11．554、36．0912、10．9209、31．1996，P〈0．05）。结论交感神经不同节段之间钙调蛋白表达存在的差异可能是交感神经元间电生理差异的基础之一。

Objective To investigate the difference of calmodulin expression in the selective parts of rat sympathetic neurons and evaluate its relationship with the electrophysiologieal diversity of sympathetic postganglionic neurons. Methods The α-SM actin and calponinct-SM actin and calponin superior cervical ganglion, cervicothoracic ganglion and celiac ganglion of sympathetic chain in SD rats were collected. The mRNA and protein expression of calmodulin was detected by RT-PCR and immunohistochemistry respectively ,and compared among three ganglia. Results Calmodulin was expressed in all the three chosen parts. The expression of calmodulin mRNA and protein in superior cervical ganglion, cervicothoracic ganglion and celiac ganglion of sympathetic chain in SD rats was 1. 191 50±0.050 09,1. 182 70 ± 0.053 93, 1. 030 90±0.066 24 and 63. 388 60 ±3. 309 38,61. 435 70 ± 2. 879 09,48. 774 90 ±3. 088 77 respectively, which corresponded with each other. There was no difference in the expression of calmodulin between the superior cervical and cervicothoracic ganglia （q =0. 6631,3. 5366 ,P 〉 0.05）. The expression of calmodu- lin in superior cervical and cervicothoracic ganglia was significantly higher than in celiac ganglion （q = 11. 554,36. 0912,10. 9209,31.1996,P 〈 0.05 ）. Conclusion The difference of ealmodulin expression in sympathetic postganglionic neurons suggests that it may play a role in the electrophysiological diversity of sympathetic neurons.