Kondo E, Kiyama H, Yamano M, Shida T, Ueda Y, Tohyama M
Department of Anesthesiology, Osaka Dental University, Japan.
Neurosci Lett. 1995 Feb 17;186(2-3):169-72. doi: 10.1016/0304-3940(95)11316-o.
The localization of GABAA receptor gamma 1 and gamma 2 subunits and the AMPA-type glutamate receptor subunits GluR1 and GluR2/3 were identified in the caudal trigeminal spinal tract nucleus (TNC) by immunohistochemistry using specific antibodies. The receptor species on the projecting neurons to the thalamus in TNC were also examined. A retrograde tracer, Fluoro-gold (FG), was injected into the thalamus, and the sections were simultaneously labeled with the antibodies. Injection of FG into the ventral posteromedial nucleus of the thalamus resulted in labeling of scattered neurons contralaterally in the TNC. Most of the neurons labeled by retrograde tracing also showed gamma 1- and gamma 2-like immunoreactivity, while many of the neurons containing FG lacked GluR1- and GluR2/3-like immunoreactivity. These findings show that neurons projecting to the thalamus from the TNC receive GABAergic input via GABAA receptors containing gamma 1 and gamma 2 subunits, while many neurons expressing the AMPA-type receptor did not project to the thalamus.
采用特异性抗体免疫组化法，在尾侧三叉神经脊髓束核（TNC）中鉴定出GABAA受体γ1和γ2亚基以及AMPA型谷氨酸受体亚基GluR1和GluR2/3的定位。还检测了TNC中向丘脑投射的神经元上的受体种类。将逆行示踪剂荧光金（FG）注入丘脑，并用抗体对切片进行同时标记。将FG注入丘脑腹后内侧核导致TNC中对侧散在神经元被标记。大多数通过逆行示踪标记的神经元也显示出γ1和γ2样免疫反应性，而许多含有FG的神经元缺乏GluR1和GluR2/3样免疫反应性。这些发现表明，从TNC向丘脑投射的神经元通过含有γ1和γ2亚基的GABAA受体接受GABA能输入，而许多表达AMPA型受体的神经元并不向丘脑投射。
