成年斑胸草雀在体HVC-RA突触传递的电生理特性

鸣禽高级发声中枢（high vocal center,HVC）至弓状皮质栎核（robust nucleus ofthe arcopallium,RA）的突触传递是鸣唱运动通路中的关键部分.本文运用在体场电位电生理记录的方法,研究了成年雄性斑胸草雀（Taeniopygia guttata）HVC-RA突触的电生理特性.实验结果显示,刺激HVC,在RA内所记录到的诱发场电位幅度较小.配对脉冲检测发现,HVC-RA突触传递具有明显的配对脉冲易化特性.当以强直刺激作用于HVC,RA内诱发场电位随即显著减小,并在15 min内逐渐恢复,表明HVC-RA突触传递在强直刺激过后出现了短时抑制.该通路的突触传递特性可能与其在发声控制中的作用有关.以上的实验结果为进一步研究发声运动过程中的突触可塑性提供了资料.

The electrophysiological properties of HVC-RA synaptic transmission in the adult zebra finch in vivo

The synaptic connection from high vocal center (HVC) to robust nucleus of the arcopallium (RA) is a pivotal pan of vocal motor pathway in songbirds.Electrophysiological properties of HVC-RA synaptic transmission in adult male zebra finch (Taeniopygia guttata) in vivo was investigated by using field potential recording method.Following electrical stimulation of HVC,the evoked field potentials recorded in RA were feeble.The results showed that the remarkable paired-pulse facilitation was induced by paired-pulse stimulation at HVC-RA synapses.The results also showed that the evoked field potentials were significantly decreased after a conditioning tetanic stimulation and finally recovered gradually within 15 min,which indicates tetanic stimulation-induced transient depression is present at HVC-RA synaptic transmission.These results suggest that properties of synaptic transmission in this pathway might play a role in controlling song production.