When low Ca2+ high Mg2+-ACSF was applied to block synaptic transmission, of 20 units which were excited by NA, 14 units still had excitatory responses and 6 units had no significant response to NA.

• 对NA有兴奋反应的20个单位,灌流低Ca~(2+)高Mg~(2+)液阻断突触传递后,其中14个单位对NA有兴奋反应,6个单位对NA没有反应。