Jan Y N, Jan L Y, Kuffler S W
Proc Natl Acad Sci U S A. 1979 Mar;76(3):1501-5. doi: 10.1073/pnas.76.3.1501.
A search was made in sympathetic ganglia of the bullfrog for a noncholinergic, nonaminergic transmitter that is released by a distinct group of preganglionic axons. These initiate a late slow excitatory postsynaptic potential which lasts for many minutes. The most promising candidate for the role of transmitter is a peptide that resembles luteinizing hormone-releasing hormone (LHRH; luliberin). The reasons are: (i) LHRH (1 muM) and some of its analogs cause a slow depolarization of ganglion cells. (ii) Radioimmunoassays established that 100-800 pg of a LHRH-like substance is contained in the lumbar chain of sympathetic ganglia. (iii) The LHRH-like material is specifically distributed in those spinal nerves that contain axons that initiate the slow noncholinergic synaptic responses. (iv) Five days after ipsilateral preganglionic axons are cut, 95% of the LHRH-like substance disappears from ganglia, while the LHRH immunoreactivity triples in the spinal nerves proximal to the cut region. (v) About 0.6% of the LHRH-like material within ganglia can be collected from the perfusate after 30 min of incubation in isotonic KC1; this release is Ca dependent. (vi) The candidate for transmitter has several chemical characteristics of a peptide and has a Mr near 1000.
在牛蛙的交感神经节中进行了一项研究，以寻找一种由一组独特的节前轴突释放的非胆碱能、非胺能递质。这些节前轴突引发一种持续数分钟的晚期慢兴奋性突触后电位。最有希望作为递质的候选物质是一种类似于促黄体生成素释放激素（LHRH；促性腺激素释放素）的肽。原因如下：（i）LHRH（1μM）及其一些类似物会引起神经节细胞的缓慢去极化。（ii）放射免疫分析表明，交感神经节腰链中含有100 - 800 pg的类LHRH物质。（iii）类LHRH物质特异性分布于那些含有能引发缓慢非胆碱能突触反应的轴突的脊神经中。（iv）同侧节前轴突切断五天后，神经节中95%的类LHRH物质消失，而在切断区域近端的脊神经中，LHRH免疫反应性增加两倍。（v）在等渗KCl中孵育30分钟后，神经节中约0.6%的类LHRH物质可从灌流液中收集到；这种释放依赖于钙。（vi）递质候选物质具有肽的若干化学特性，其分子量接近1000。
