The temporal dynamics of membrane voltage changes in neurons is controlled by ionic currents. These currents are characterized by two main properties: conductance and kinetics. The hyperpolarization-activated current (\(\hbox {I}_{\mathrm {h}}\)) strongly modulates subthreshold potential changes by shortening the excitatory postsynaptic potentials and decreasing their temporal summation. Whereas the shortening of the synaptic potentials caused by the \(\hbox {I}_{\mathrm {h}}\) conductance is well understood, the role of the \(\hbox {I}_{\mathrm {h}}\) kinetics remains unclear. Here, we use a model of the \(\hbox {I}_{\mathrm {h}}\) current model with either fast or slow kinetics to determine its influence on the membrane time constant (\(\tau _{m})\) of a CA1 pyramidal cell model. Our simulation results show that the \(\hbox {I}_{\mathrm {h}}\) with fast kinetics decreases \(\tau _{m}\) and attenuates and shortens the excitatory postsynaptic potentials more than the slow \(\hbox {I}_{\mathrm {h}}\). We conclude that the \(\hbox {I}_{\mathrm {h}}\) activation kinetics is able to modulate \(\tau _{m}\) and the temporal properties of excitatory postsynaptic potentials (EPSPs) in CA1 pyramidal cells. To elucidate the mechanisms by which \(\hbox {I}_{\mathrm {h}}\) kinetics controls \(\tau _{m}\), we propose a new concept called “time scaling factor”. Our main finding is that the \(\hbox {I}_{\mathrm {h}}\) kinetics influences \(\tau _{m}\) by modulating the contribution of the \(\hbox {I}_{\mathrm {h}}\) derivative conductance to \(\tau _{m}\).

神经元中膜电压变化的时间动态由离子电流控制。这些电流具有两个主要特性：电导和动力学。超极化激活电流 ( \(\hbox {I}_{\mathrm {h}}\) ) 通过缩短兴奋性突触后电位并降低它们的时间总和来强烈调节亚阈值电位变化。虽然由\(\hbox {I}_{\mathrm {h}}\)电导引起的突触电位的缩短是众所周知的，但\(\hbox {I}_{\mathrm {h} }\)动力学仍不清楚。这里，我们使用\(\hbox {I}_{\mathrm {h}}\)当前模型具有快速或慢速动力学，以确定其对CA1 锥体细胞模型的膜时间常数 ( \(\tau _{m})\)的影响。我们的模拟结果表明，具有快速动力学的\(\hbox {I}_{\mathrm {h}}\)比缓慢的\ (\tau _{m}\) 降低和衰减和缩短兴奋性突触后电位更多(\hbox {I}_{\mathrm {h}}\)。我们得出结论，\(\hbox {I}_{\mathrm {h}}\)激活动力学能够调节\(\tau _{m}\)和 CA1 中兴奋性突触后电位 (EPSP) 的时间特性锥体细胞。阐明\(\hbox {I}_{\mathrm {h}}\)动力学控制的机制\(\tau _{m}\)，我们提出了一个称为“时间缩放因子”的新概念。我们的主要发现是，\（\ hbox中{I} _ {\ mathrm {H}} \）动力学的影响\（\ tau蛋白_ {米} \）通过调制的贡献\（\ hbox中{I} _ { \mathrm {h}}\)对\(\tau _{m}\) 的导数。