大白鼠脊髓后角内乙酰胆碱M受体与体感一级传入的关系

Relationship between Acetylcholine Muscarinic Receptor and Primary Sensory Afferent of Somatosensation in Rat Spinal Dorsal Horn

为了进一步研究乙酰胆碱（ＡＣｈ）与体感一级传入的关系，用大白鼠脊髓后角内乙酰胆碱毒蕈碱受体（Ｍ．ＡＣｈＲ）放射自显影银粒的分布与数量变化为观察指标进行了分析研究，结果发现：①脊髓后角浅层有Ｍ．ＡＣｈＲ（＾３Ｈ－二苯羟乙酸奎宁酯；＾３Ｈ－ＱＮＢ结合位点），其分布与抗氟化钠酸性磷酸酶（ＦＲＡＰ）和乙酰胆碱酯酶（ＡＣｈＥ）一致；②切断一侧后根５ｄ，术侧后角浅层ＦＲＡＰ明显减少。

In order to study the relationship between Acetylcholine(ACh)and the primary sensory afferent,the method of autoradiogrphy was used for investigating distribution and change of acetylcholine muscarinc receptor (M.AChR).The results were as follows:l) M.AChR(3-quinuclindinyl benzilate；(~3H-QNB) combining points)appeared within Rexed's laminasⅠ,Ⅱ,which distribute in the same way with FRAP and acetylcholinesterase(AChE),2)5 days after unilateral dorsal rhizotomy,FARP activity in Rexed's laminas Ⅰ.Ⅱ in ipsilateral of the rats was notably decreased；on the contrary,~3H-QNB combining points markedly increased;3) 5 months after intraperitonal injection of capsincin in dorsal born substantia glatinosa (SG) of the rats was signifcantly decreased with increased ~3H-QNB combining points.It is indicated that M.AChR is a kind of postsynapse receptor of the primary sensory afferent of somatosensation.On the other hand,ACh might be a neurotransmitter of primary afferent nerve,and play an important role in transmitting sensory information through the muscarinicreceptor.