直肠扩张联合肢体束缚诱导大鼠内脏高敏感模型的持续性  

Persistance of visceral hypersensitivity in the rat models induced by rectal distention combined with limb constraint

作　　者：陶丽媛[1] 吕宾[1] 李蒙[1] 庄肇朦[1] 

机构地区：[1]浙江中医药大学附属第一医院消化科,浙江杭州310006

出　　处：《中国比较医学杂志》2013年第10期21-25,I0004,共6页Chinese Journal of Comparative Medicine

基　　金：国家自然科学基金(81170384);浙江省自然科学基金(Z12H030001)

摘　　要：目的观察直肠扩张联合肢体束缚诱导的内脏高敏感大鼠的高敏感持续性。方法 32只8周龄SD大鼠随机分为对照组(n=16)、模型组(n=16),直肠扩张联合肢体束缚2周法刺激模型组大鼠,以大鼠腹部收缩反射(AWR)评分评估肠道敏感性。依据AWR评分,随机将对照组均分为对照组A(n=8)和对照组B(n=8),将模型组均分为模型组C(n=8)和模型组D(n=8);麻醉下解剖获取A组和C组结肠标本。B组、D组继续正常饲养至18周龄后,以相同方法刺激D组大鼠,获取AWR评分和结肠标本。电镜观察标本肥大细胞(MC)超微结构,甲苯胺蓝染色行MC计数,Western Blot检测结肠蛋白酶原激活受体2(PAR2)表达水平。结果 C组AWR评分高于A组,D组低于C组,差异均有统计学意义(P<0.01);C组MC计数高于A组,D组低于C组,差异均有统计学意义(P<0.01);C组见肥大细胞脱颗粒现象,余各组均未见明显脱颗粒;C组PAR2表达水平高于A组,D组低于C组,差异均有统计学意义(P<0.01)。结论直肠扩张联合肢体束缚建立的内脏高敏感模型的敏感性随周龄增加下降。Objective To assess the persistence of visceral hypersensitivity in rat models induced by rectal distension combined with limb constraint. Methods Thirty-two 8-week old Sprague-Dawley （SD） rats were randomly divided into control group （n = 16） and model group （n = 16）. Rectal distension with limb constraint lasting for 2 weeks was operated on the model group rats. Visceral sensitivity was evaluated by abdominal withdrawal reflex （AWR）. Based on the AWR scores, the rats in the control group were randomly divided into group A （ n = 8） and group B （ n = 8） , and the model group was randomly divided into group C （n = 8） and group D （n = 8）. Colon specimens of the groups A and C were taken under anesthesia. Group B and group D received normal breeding until 18-weeks old, and then group D received the same stimulation. AWR scores and colon specimens were obtained in the same way. The ultrastructure of mast cells was observed by electron microscopy. Toluidine blue staining was performed to count mast cells （MC）. Protease- activated receptor 2 （PAR2） was analyzed by Western blot. Results AWR score of the group C was significantly higher than that of group A, and that of the group D was lower than that of the group C （P 〈 0.01 ）. Intestinal MC count of the group C was significantly higher than that in the group A, and that of the group D was significantly lower than that of the group C （ P 〈 0.0l ）. Mast cell degranulation was visible in the group C, neither in other groups. PAR2 expression level of the group C was significantly higher than that of the group A, and that of the group D was significantly lower than that of the group C （P 〈 0. 01 ）. Conclusion The sensitivity of visceral hypersensitivity in the rat models induced by rectal distension combined with limb constraint is attenuated along with the increase of age in weeks.

关 键 词：内脏高敏感 直肠扩张 肥大细胞 蛋白酶原激活受体2 大鼠 

分 类 号：R33[医药卫生—人体生理学]