Rust G, Burgunder J M, Lauterburg T E, Cachelin A B
Department of Pharmacology, University of Berne, Switzerland.
Eur J Neurosci. 1994 Mar 1;6(3):478-85. doi: 10.1111/j.1460-9568.1994.tb00290.x.
In the autonomic nervous system efferent signals are relayed in sympathetic and parasympathetic ganglia. Fast synaptic transmission between pre- and postsynaptic neurons is achieved by neuronal nicotinic acetylcholine receptors (nAChRs). There is still little known about the subunit composition of these receptors. Establishing the subunit composition of native neuronal nAChRs is important for the understanding of their functional properties both in vivo and after expression in heterologous expression systems. We have combined in situ hybridization and autoradiography to detect the presence of mRNAs encoding subunits of neuronal nAChRs in sympathetic and parasympathetic ganglia. Inspection of the autoradiographs showed that the hybridization signal of five riboprobes (alpha 3, alpha 4-1, alpha 7, beta 2 and beta 4) was significantly higher than the unspecific signal obtained with sense riboprobes. The distribution of alpha 7 was tissue-dependent: alpha 7 riboprobe binding was detected in the neurons of the superior cervical ganglion, adrenal medulla and ciliary ganglion. In contrast, the alpha 7 hybridization signal was found only in a small fraction (1-3%) of the neurons of the sphenopalatine and otic ganglia. Our results are consistent with the idea that alpha 3 mRNA expression levels are somewhat higher than those of alpha 7, alpha 4-1, beta 2 and beta 4.
在自主神经系统中，传出信号在交感神经节和副交感神经节中进行中继传递。突触前神经元和突触后神经元之间的快速突触传递是通过神经元烟碱型乙酰胆碱受体（nAChRs）实现的。关于这些受体的亚基组成，目前仍知之甚少。确定天然神经元nAChRs的亚基组成对于理解其在体内以及在异源表达系统中表达后的功能特性至关重要。我们结合了原位杂交和放射自显影技术，以检测交感神经节和副交感神经节中编码神经元nAChRs亚基的mRNA的存在情况。对放射自显影片的检查显示，五种核糖探针（α3、α4-1、α7、β2和β4）的杂交信号明显高于用正义核糖探针获得的非特异性信号。α7的分布具有组织依赖性：在颈上神经节、肾上腺髓质和睫状神经节的神经元中检测到α7核糖探针结合。相比之下，仅在蝶腭神经节和耳神经节的一小部分（1-3%）神经元中发现了α7杂交信号。我们的结果与α3 mRNA表达水平略高于α7、α4-1、β2和β4的观点一致。
