Semyanov A, Godukhin O
Institute of Theoretical and Experimental Biophysics of Russian Academy of Science, Pushchino, Moscow Region, Russia.
Neurosci Lett. 1997 Feb 28;223(3):177-80. doi: 10.1016/s0304-3940(97)13436-x.
The repeated 30 s applications (3-6 episodes) of K+ (up to 20 mM) induced the appearance of single electric pulse-triggered population spike bursts in the rat CA1 hippocampal slices. This kindling-like state kept for a long time after the last K(+)-application and was limited by the time of slice survival. Disconnection of CA3 region did not significantly eliminate the effect of repeated short-term [K+]o increases on the establishment and maintenance of the kindling-like state in the CA1 region. This state correlated with the increases in the efficiency of the excitatory postsynaptic potential (EPSP)-spike transfer (the excitability of CA1 pyramidal neurons) but not in the glutamatergic synaptic efficiency. The selective blocker of L-type Ca2+ channels nimodipine (10 microM) abolished the development of the kindling-like state as well as the increases in the efficiency of the EPSP-spike transfer in rat hippocampal CA1 slices. Taken together, these data indicate that the described model of kindling in vitro can be useful for a study of the role of different sites of Ca2+ entry into hippocampal neurons for the cellular mechanisms of epileptogenesis.
在大鼠海马CA1区脑片中，重复施加30秒的钾离子（浓度高达20 mM，共3 - 6次）会诱发单个电脉冲触发的群体峰电位爆发。这种类似点燃的状态在最后一次施加钾离子后会持续很长时间，并受脑片存活时间限制。切断CA3区并不能显著消除重复短期增加细胞外钾离子浓度对CA1区类似点燃状态的建立和维持所产生的影响。这种状态与兴奋性突触后电位（EPSP）-峰电位传递效率（CA1锥体神经元的兴奋性）的增加相关，但与谷氨酸能突触效率无关。L型钙离子通道的选择性阻滞剂尼莫地平（10 microM）可消除大鼠海马CA1区脑片中类似点燃状态的发展以及EPSP -峰电位传递效率的增加。综上所述，这些数据表明所描述的体外点燃模型可用于研究钙离子进入海马神经元的不同位点在癫痫发生细胞机制中的作用。
