去胡须对大鼠行为及桶状皮层的影响  

Effect of whisker trimming on behavior and barrel cortex of rat

作　　者：孙缦利[1] 张小兵[2] 孙霞[3] 赵孟辉[1] 虞燕琴[1] 

机构地区：[1]浙江大学医学院生理系,杭州310058 [2]浙江大学医学院05级临床医学系七年制,杭州310058 [3]杭州师范大学基础医学部生理教研室,杭州310036

出　　处：《中国应用生理学杂志》2010年第3期354-358,共5页Chinese Journal of Applied Physiology

基　　金：国家自然科学基金资助项目(30870834);浙江省医药卫生科学研究基金计划(2008A042)

摘　　要：目的:研究外周去胡须后大鼠行为及桶状皮层(barrel cortex,BC)的可塑性变化。方法:SD大鼠随机分组(n=4):正常对照(A组),出生后第2天去除双侧颊脂垫组(B组),出生后第2天去除右侧颊脂垫组(C组),出生后1～5d每天剪右侧胡须,从出生后第5天起不剪由其胡须自由生长组(D组)。出生后第30天时称体重,测量左侧D2胡须长度,观测行为学变化(如狭缝实验、自由探索行为和趋壁行为)。采用细胞色素氧化酶组织化学法研究barrel排列与发育情况。结果:A组能迅速辨别出正确狭缝并钻入,平均用时(5.6±2.3)s;B组大鼠只有当鼻尖碰到狭缝壁时才会钻入狭缝。C组大鼠当其右侧脸颊靠近狭缝时,不能辨别出狭缝,只有当其掉转身体,用左侧胡须探测时才可能迅速钻入正确的狭缝。D组的表现同C组,B、C、D组大鼠进入正确狭缝的所用时间均显著长于A组(P<0.01,P<0.05,P<0.01)。去除双侧颊脂垫的大鼠其左趋壁时间、右趋壁时间以及总趋壁时间均较正常大鼠短。去除右侧颊脂垫组的大鼠右趋壁时间也显著短于正常(P<0.05)。四组大鼠左侧D2胡须长度以及体重均无显著差异。从出生后第2天时一直剪除右侧胡须的小鼠在出生后第30天时发现其barrel变小,排列较混乱,barrel之间的界限不清,皮层细胞色素氧化酶(CO)反应的灰度明显变淡。结论:外周去传入不引起大鼠体重改变及残留胡须长度的代偿性改变,但可引起其趋触及探索行为方面的改变。外周去传入可导致barrel形状及排列的可塑性变化。Objective： To investigate the change of behavior, as well as the plasticity of somatosensory cortex after whisker trimming. Methods： SD rats were divided into 4 groups. Group A is the normal coutrol group; group B： bilateral vibrissotomy on the second postnatal day; group C： unilateral right vibrissotomy on the second postnatal day; group D： right unilateral whisker trimmed during 1-5 days after birth, and leave untreated ＇after the 5th postnatal day. Their body weight, length of the left D2 whiskers was measured on the 30th postnatal day. At the same time, the changes of their behavior （including the slit-detection test, the home exploring behavior and thigmotaxis test）were also recorded on the 30th postnatal day. Cytochi＇nme oxydase histochemistry（CO reaction）was applied to study the development and arrangement of barrel cortex. Restilts： In the slit-detection test,control rats could find and get into the fight slit very quickly. The rats in group B could get into the slit only if their noses touched the slit. The rats in group C conldin＇t identify the slit by right face, but if they turned their body and touched the slit with the left whiskers, they could get into the slit very quickly. The behavior of rats in group D was similar to that in group C. The time spent for finding out the right slit of the rats in group A, B, C was obviotrsly longer than that of group A（ P 〈 0.01, P 〈 0.05, P 〈 0.01 ）. In the exploring behavior and thigmotaxis test, the time for left thigmotaxis, right thitgnotaxis and total thigmotaxis of rats in group B was longer than that of control ani- mals. The time for right thigmotaxis of group C was significantly shorter than that of group A（ P 〈 0.05）. Both the weight of the rats and the length of left D2 whiskers of rats in all the four groups had no significant diffence. CO reaction showed that the barrels became smaller, the septum was not clear, the arrangement of the barrels was not tidy in the mice whose right whiskers were trimmed from 2-3

关 键 词：Barrel皮层 胡须 可塑性 去传入 

分 类 号：R331[医药卫生—人体生理学]