SK channels modulate the excitability and firing precision of projection neurons in the robust nucle

• 作 者: Guo-Qiang Hou Cong-Shu Liao Xuan Pan Dong-Feng Li
• 机 构: College of Life Science, South China Normal University, Guangzhou 510631
• 出 处: Iternational Frontiers Symposium foe Neuron & Disease(国际神经与疾
• 发表日期: 2012年8期

　　The firing activities of neurons encode the information of motor control.SK channels maintain the regularity and precision of firing by contributing to the afterhyperpolarization (AHP) of action potential in mammals.But it is not clear that how SK channels regulate the output of vocal motor in songbirds.The premotor robust nucleus of the arcopallium (RA) in zebra finch is responsible for the output of song information.Temporal pattern of spike bursts in RA projection neurons is associated with the timing of acoustic features of birdsong.The present study showed that SK channel blockade decreased the amplitude of AHP and increased the evoked firing rate in RA projection neurons, and caused a reduction in the regularity and precision of firing.RA projection neurons display regular action potentials spontaneously.SK channel blocker apamin made spontaneous firing more irregular, but had no effect on the spontaneous firing rate.In the absence of synaptic inputs,RA projection neurons still have spontaneous firing, and apamin had a similar effect on the firing activities, compared with apamin application alone.Our study suggests that SK channels contribute to the maintenance of the regularity of firing in RA projection neurons,and consequently ensure the precision of song encoding.