大鼠丘腦腹後側核及網狀核神經元的生理及形態特性比較

Abstract

大鼠腦中的腹背側核 (VPL) 和網狀核 (Rt) 是傳遞體感覺的重要中繼站，來自週遭的體感覺訊息在此會合, 然後上傳至大腦皮質，產生感覺。這個實驗在研究並比較大鼠VPL和Rt中神經元的生理及形態特性，並進一步依照神經元對自然刺激和電刺激的反應, 來訂出在這兩個核區中的亞群。在麻醉的大鼠VPL和Rt內，我們紀錄了細胞外單一神經元的自發性電生理訊號，並分析神經元在週遭受到自然刺激或電刺激時的活性改變。進一步地，我們在腦片中，用whole-cell patch-clamp recording的方式，紀錄Rt和VPL的電生理特性，同時在實驗結束後，染色分析Rt和VPL細胞核的形態。 實驗結果顯示，VPL和Rt神經元有著顯著不同，例如: 波形、對不同刺激的反應、和形態。但是在對刺激有著不同反映的次亞群中，我們無法找出他們在波形上的差異。

Thalamic reticular nucleus (Rt) and ventroposter somatosensory signals en route to the cerebral cortex. This study sought to compare and characterize ior lateral nucleus (VPL) are two important thalamic nuclei processing electrical and morphological properties of Rt and VPL, and to classify functional subclasses in the two regions by their electrical properties. Extracellular single-unit activities of Rt and VPL were recorded in anesthetized rats. Spontaneous firing pattern and responsive pattern to tactile or noxious stimuli were used to subdivide the units into functional subclasses. In addition, Rt and VPL neurons were recorded in slice preparations by whole-cell patch technique. Morphological differences between Rt and VPL neurons were analyzed. Our results showed that VPL and Rt neurons differed significantly in their electrical activities, such as spike waveforms, response patterns to different stimuli, and cell morphology. However, subclasses in the two regions differed in their response patterns but not their waveforms.