Objective To explore the possibility of establishment of a chronic visceral hypersensitivity model of mice induced by neonatal maternal separation and its meaning .Methods Neonatal mice were randomly divided into two groups.An half number of mice were subjected to 3 h of neonatal maternal separation per day from Days 2 to 15, while another half number of mice were set as controls .All mice underwent behavior test at eight weeks old , in order to evalu-ate their visceral sensitivity as well as anxiety and depression -like behavior induced by neonatal maternal separation . Results Compared with the control , neonatal maternal separation caused visceral hypersensitivity , especially higher ab-dominal withdrawal reflex (AWR) scores (P<0.01), lowered threshold of pain (P<0.01), and an elevated discharge rate in the musculus obliquus externus abdominis ( P<0 .05 ) .No significant behavior changes were found in the sugar preference test (P>0.05).After neonatal maternal separation , the mice presented anxiety and depression -like behav-ior, according to a shorter period of time in the central zone during the open field test (P<0.05) and an extended period of motionless in the forced swimming test ( P<0.01) respectively.Conclusion Neonatal maternal separation can lead to chronic visceral hypersensitivity in adult mice , accompanied with anxiety and depression -like behavior at the same time.%目的：探讨建立小鼠新生期母婴分离致慢性内脏痛觉高敏模型的可能性及意义。方法将新生小鼠随机分成2组，母婴分离组出生后第2～15天每天与母鼠分离3 h，对照组出生后不予处理。8周龄时进行行为学测试，测定评估内脏痛觉敏感性及对焦虑、抑郁行为的影响。结果与对照组比较：母婴分离组小鼠腹壁撤退反射评分增高（P＜0．01）、痛阈降低（P＜0．01）、腹外斜肌放电波幅明显升高（P＜0．05），表现出内脏痛觉高敏；在糖水偏好实验中未表现出行为差异（P＞0．05）；在旷场实验中中心区停留时间缩短（P＜0．05），出现焦虑行为；在强迫游泳实验中表现为不动时间延长（P＜0．01），存在行为绝望。结论新生期母婴分离能够导致小鼠发生成年后慢性内脏痛觉高敏，同时伴随焦虑和抑郁样症状。
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