Paired pulse facilitation of corticogeniculate EPSCs in the dorsal lateral geniculate nucleus of the rat investigated in vitro
Paired pulse facilitation of corticogeniculate EPSCs in the dorsal lateral geniculate nucleus of the rat investigated in vitro
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DOI：
10.1113/jphysiol.2002.024703
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发表时间：
2002-10-15
影响因子：
5.5
通讯作者：
Lindström, S
中科院分区：
文献类型：
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作者：
Granseth, B;Ahlstrand, E;Lindström, S
为研究皮质膝状体EPSC的成对脉冲易化作用，在离体大鼠外侧膝状体背侧核（dLGN）的主细胞上进行了全细胞膜片钳记录。丘脑切片，定向，使皮质和retinogeniculate轴突都可以被刺激，从年轻的（16 - 37日龄）DA-HAN大鼠。皮质膝状体EPSC在高达400 ms的刺激间隔下显示出明显的成对脉冲易化。该易化具有快速和缓慢的衰减成分，时间常数为12 +/-7和164 +/-47 ms（平均值+/-S.D.），分别在20 - 30 ms间期，最大成对脉冲比（EPSC 2 x EPSC 1 - 1）为3.7 +/-1.1。与其他系统类似，这种易化作用也是突触前的。在相同的dLGN细胞中记录的retinogeniculate EPSCs显示成对的脉冲抑制，间隔至少为700 ms。这两种类型的EPSCs不同的钙反应曲线。在正常[Ca 2 +]（o）时，皮质膝状体突触在Hill函数的早期上升部分起作用，而视网膜膝状体突触在曲线的中部和上部起作用。在生理[Ca 2 +]（o）时，皮质膝状体EPSC的成对脉冲比最大。这种易化被认为在皮质膝状体回路作为神经放大器的功能中具有重要作用。
To investigate paired pulse facilitation of corticogeniculate EPSCs, whole-cell patch-damp recordings were made from principal cells in the rat dorsal lateral geniculate nucleus (dLGN) in vitro. Thalamic slices, oriented so that both corticogeniculate and retinogeniculate axons could be stimulated, were cut from young (16- to 37-day-old) DA-HAN rats. Corticogeniculate EPSCs displayed pronounced paired pulse facilitation at stimulus intervals up to 400 ms. The facilitation had a fast and a slow component of decay with time constants of 12 +/- 7 and 164 +/- 47 ms (means +/- S.D.), respectively. Maximum paired pulse ratio (EPSC2 x EPSC1-1) was 3.7 +/- 1.1 at the 20-30 ms interval. Similar to other systems, the facilitation was presynaptic. Retinogeniculate EPSCs recorded in the same dLGN cells displayed paired pulse depression at intervals up to at least 700 ms. The two types of EPSCs differed in their calcium response curves. At normal [Ca2+](o), the corticogeniculate synapse functioned over the early rising part of a Hill function, while the retinogeniculate synapse operated over the middle and upper parts of the curve. The paired pulse ratio of corticogeniculate EPSCs was maximal at physiological [Ca2+](o). The facilitation is proposed to have an important role in the function of the corticogeniculate circuit as a neuronal amplifier.