Langmoen I A, Segal M, Andersen P
Brain Res. 1981 Mar 16;208(2):349-62. doi: 10.1016/0006-8993(81)90563-1.
Responses of pyramidal cells to topical application of norepinephrine (NE) were studied by intracellular recording in hippocampal slices in vitro. Norepinephrine hyperpolarized CA1 cells. Simultaneously, there was a decreased response to constant hyperpolarizing and depolarizing current pulses. The number of spikes evoked by constant depolarizing pulses was reduced. Spontaneous activity, when present, was reduced or abolished. The response to depolarizing current pulses was reduced more than the response to hyperpolarizing current pulses. The reduction of the depolarizing response was minimal for the first 6-8 msec of the pulse, whereafter it increased. The effects persisted after blocking synaptic transmission with low calcium-high magnesium concentrations in the incubation fluid. We conclude that the hyperpolarization is most likely due to a conductance increase. The mechanism behind the reduced response to depolarizing current pulses is discussed.
通过在体外海马切片中进行细胞内记录，研究了锥体细胞对局部应用去甲肾上腺素（NE）的反应。去甲肾上腺素使CA1细胞超极化。同时，对恒定的超极化和去极化电流脉冲的反应降低。恒定去极化脉冲诱发的动作电位数量减少。自发活动（如果存在）减少或消失。对去极化电流脉冲的反应比对超极化电流脉冲的反应降低得更多。在脉冲的前6 - 8毫秒内，去极化反应的降低最小，此后增加。在用孵育液中低钙 - 高镁浓度阻断突触传递后，这些效应仍然存在。我们得出结论，超极化很可能是由于电导增加所致。文中讨论了对去极化电流脉冲反应降低背后的机制。
