摘要
目的比较成年和老龄大鼠神经肌肉接头处突触后膜乙酰胆碱受体表达和空间分布的差异。方法健康雄性Wistar大鼠10只，按月龄分为成年组（4—6月龄，n=5）和老龄组（24～28月龄，n=5），提取大鼠腓肠肌总RNA。根据编码大鼠烟碱型乙酰胆碱受体ε亚单位的mRNA序列，设计引物并合成引物对，采用实时定量PCR技术测定腓肠肌组织烟碱型乙酰胆碱受体ε亚单位mRNA表达量。用四甲基罗丹明-α-银环蛇毒标记大鼠神经肌肉接头处突触后膜乙酰胆碱受体，采用激光共聚焦显微镜激发标记物发光，观察受体分布情况，并测定受体分布区的面积、长度和宽度。结果与成年组比较，老龄组大鼠腓肠肌烟碱型乙酰胆碱受体ε亚单位mRNA表达量降低（P〈0．05），突触后膜乙酰胆碱受体分布区面积、长度和宽度差异无统计学意义（P〉0．05）。两组大鼠突触后膜乙酰胆碱受体分布形态存在明显差异。结论老龄可下调大鼠神经肌肉接头处突触后膜乙酰胆碱受体表达，但并不改变运动神经轴突末梢与骨骼肌纤维的接触面积。
Objective To examine the difference in the number and distribution of acetylcholine receptor （AChR） in post-synaptic membrane of neuromuscular junction between young adult and elderly rats. Methods Ten male Wistar rats were divided into 2 age groups （ n = 5 each） ： group Ⅰ 4-6 months old and group Ⅱ 24- 28 months old . The expression of nicotinic AChR in gastrocnemius muscle was detected by quantitative real-time PCR （qRT-PCR）. Primers were designed according to the mRNA subsequence of ε-subunit of AChR. The post- synaptic AChR in gastrocnemius muscle was labeled with tetramethyl-rhodamine-α-bungarotoxin. The distribution of post-synaptic AChR was investigated by confocal microscopy. The area, length and width of AChR region were calculated by computer. Results There was significant difference in AChR expression between the 2 groups. Furthermore a significant difference in distribution structure of AChR was found by confocal microscopy. There was no significant difference in the area, length and width of post-synaptie receptor region between the 2 groups. Conclusion Elderly rats have a low level of AChR expression but the area of neuro-muscular junction does not change significantly with age.
出处
《中华麻醉学杂志》
CAS
CSCD
北大核心
2010年第2期178-180,共3页
Chinese Journal of Anesthesiology
关键词
受体
胆碱能
神经肌肉接头
突触膜
老年人
Receptors, cholinergic
Neuromuscular junction
Synaptic membranes
Aged
