Neurochemical identification of stereotypic burst-firing neurons in the rat dorsal raphe nucleus using juxtacellular labelling methods
Neurochemical identification of stereotypic burst-firing neurons in the rat dorsal raphe nucleus using juxtacellular labelling methods
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DOI：
10.1111/j.1460-9568.2006.05276.x
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发表时间：
2007-01-01
影响因子：
3.4
通讯作者：
Kocsis, Bernat
中科院分区：
文献类型：
--
作者：
Hajos, Mihaly;Allers, Kelly A.;Kocsis, Bernat
最近的电生理研究发现中脑中缝核5-羟色胺（5-HT）神经元的异质性证据。特别令人感兴趣的是一个亚群的推定5-HT神经元，显示许多电生理特性的推定5-HT含神经元（定期和缓慢发射单尖峰与宽波形），但发射尖峰短，刻板的爆发。在本研究中，我们研究了这些神经元的化学身份在大鼠体内利用细胞标记方法。10个中缝背核（DRN）神经元在一个其他规则的放电模式内发射短刻板爆发，所有表现出免疫反应性的5-HT（n = 6）或5-HT合成酶，色氨酸羟化酶（TRH; n = 2）或两者（n = 2）。支持药理学实验表明，爆发式放电的DRN神经元表现出相同的敏感性，5-HT 1A激动和α（1）-肾上腺素受体拮抗剂的单一尖峰DRN神经元，我们已经确定为5-HT-含有。总的来说，这些数据提供了直接的证据表明，DRN神经元表现出刻板的爆发式放电活动是5-HT。多种类型的电生理不同的中脑5-HT神经元的存在进行了讨论。
Recent electrophysiological studies have discovered evidence of heterogeneity of 5-hydroxytryptamine (5-HT) neurons in the mesencephalic raphe nuclei. Of particular interest is a subpopulation of putative 5-HT neurons that display many of the electrophysiological properties of presumed 5-HT-containing neurons (regular and slow firing of single spikes with a broad waveform) but fire spikes in short, stereotyped bursts. In the present study we investigated the chemical identity of these neurons in rats utilizing in vivo juxtacellular labelling methods. Of ten dorsal raphe nucleus (DRN) neurons firing short stereotyped bursts within an otherwise regular firing pattern, all exhibited immunoreactivity for either 5-HT (n = 6) or the 5-HT synthesizing enzyme, tryptophan hydroxylase (TRH; n = 2) or both (n = 2). Supporting pharmacological experiments demonstrated that the burst firing DRN neurons demonstrated equal sensitivity to 5-HT1A agonism and alpha(1)-adrenoceptor antagonism to single spiking DRN neurons that we have previously identified as 5-HT-containing. Collectively these data provide direct evidence that DRN neurons that exhibit stereotyped burst firing activity are 5-HT containing. The presence of multiple types of electrophysiologically distinct midbrain 5-HT neurons is discussed.