Methods Cholera toxin subunit-B(CTB) was injected into cat cochlea, and the brain tissue was examined after a survival period of 7 days. Distribution and morphology of raphe neurons was determined by a retrograde fluorescent tracer technique.

• 方法将霍乱毒素亚单位B(cholera toxin subunit-B,CTB)注入猫的内耳,经过7天的存活期后,运用逆行荧光标记技术来观察猫脑干组织中DRN神经元的分布及形态学特征。