Mediation of hippocampal mossy fiber long-term potentiation by presynaptic Ih channels
Mediation of hippocampal mossy fiber long-term potentiation by presynaptic Ih channels
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DOI：
10.1126/science.1064285
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发表时间：
2002-01-04
期刊：
影响因子：
56.9
通讯作者：
Schmitz, D
中科院分区：
文献类型：
--
作者：
Mellor, J;Nicoll, RA;Schmitz, D
海马苔藓纤维长时程增强（LTP）在突触前表达，但其确切机制尚不清楚。在这里，我们证明了参与的超极化激活阳离子通道（I-H）的苔藓纤维LTP的表达。建立的LTP被I-h阻断和逆转。通道拮抗剂。从颗粒细胞的全细胞记录表明，重复刺激引起的钙和I-h依赖性的蛋白激酶A介导的持久的去极化。在终端的去极化将被期望增强递质释放，而躯体去极化将增强颗粒细胞对传入输入的反应性。因此，I-h通道在长期控制递质释放和神经元兴奋性方面发挥重要作用。
Hippocampal mossy fiber long-term potentiation (LTP) is expressed presynaptically, but the exact mechanisms remain unknown. Here, we demonstrate the involvement of the hyperpolarization-activated cation channel (I-h) in the expression of mossy fiber LTP. Established LTP was blocked and reversed by I-h. channel antagonists. Whole-cell recording from granule cells revealed that repetitive stimulation causes a calcium- and I-h-dependent long-lasting depolarization mediated by protein kinase A. Depolarization at the terminals would be expected to enhance transmitter release, whereas somatic depolarization would enhance the responsiveness of granule cells to afferent input. Thus, I-h channels play an important rote in the long-lasting control of transmitter release and neuronal excitability.