中文摘要：

目的：比较基于母子分离、慢性束缚等不同精神心理应激建立IBS-D大鼠模型的特征差异,探索建立IBS-D大鼠模型的理想方法。方法：将40只新生期SD大鼠随机分为母子分离组和非母子分离组,每组20只,母子分离组大鼠第2~14天每天与母鼠分离3 h,其余大鼠不分离。第9周,将非母子分离组随机分为正常组（N组）、慢性束缚组（R组）,将母子分离组随机分为单一母子分离组（S组）和联合应激组（SR组）,每组10只。R组和SR组大鼠采用自制束缚架进行制动束缚应激,3 h/d,连续3周,其余2组不予束缚。在束缚期的最后1周,N组大鼠予生理盐水灌胃,其余3组大鼠均予番泻叶煎剂（0.45 g/m L）灌胃（4.5 g/kg）,连续7 d。检测评价4组大鼠成年期束缚应激前后内脏敏感性、大便积分、旷场行为学,以及造模后血清5羟色胺水平、近端结肠常规病理、肥大细胞及嗜铬细胞数量。结果：1）内脏敏感性：束缚应激前,经历母子分离应激组（S组、SR组）大鼠痛觉阈值明显低于非母子分离应激组（N组、R组）（P〈0.05）;束缚应激后,S组和SR组大鼠痛觉阈值显著低于N组（P〈0.05）,R组与N组比较,差异无统计学意义（P〉0.05）。2）大便积分：S组、R组及SR组大便积分均明显高于正常组（P〈0.05）,SR组明显高于R组和S组（P〈0.05）。3）旷场行为学特征：束缚应激前,S和SR组大鼠旷场穿格数有低于N和R组的趋势,但站立数均明显低于N和R组（P〈0.05）;束缚应激后,R组、S组、R组大鼠旷场穿格数及站立数均明显低于N组（P〈0.05）,SR组穿格数明显低于S组（P〈0.05）。4）血清5-HT水平：S组和SR组大鼠血清5-HT水平明显高于N组（P〈0.05）,R组与N组差异无统计学意义,SR组明显高于S组和R组（P〈0.05）。5）近端结肠病理及MC、EC数目：4组大鼠结肠病理未见异常。SR组大鼠近端结肠MC数目明显多于N组（P〈0.05）,其余各?

英文摘要：

Objective： To explore a reliable rat model of IBS-D by comparing the differences of different psychological stress.Methods： A total of 40 neonatal rats were randomly divided into 2 groups： normal group and maternal separation group. The pups in the maternal separation group were exposed to 3 h period daily maternal separation from postnatal day 2 ~ 14,and then they were randomly divided into single maternal separation group（ S） and combined stress group（ SR） in the 9th week. The pups it the other group were left untreated and then were randomly divided into normal group（ N） and chronic restraint stress group（ R） in the 9th week. The group R and SR underwent chronic restraint stress by specially designed restraint frame 3 h daily for 3 weeks. The group N and S were left untreated. In the 12 th week,the group N was given normal saline by gavage,the group R,S and SR were given Senna decoction（ 0. 45 g/m L） by gavage（ 4. 5 g/kg） for 7 days. The visceral sensitivity was tested and the animal behavior was evaluated by open field test before and after the chronic restraint stress. The fecal scores were calculated. The level of serum5-HT,the number of mast cells（ MC） and enterochromaffin cell（ EC） of the proximal colon colon were tested after the modeling.Results： 1） Visceral sensitivity： Before the restraint stress,the pain threshold of the maternal separation group（ S、SR） were lower compared to the other group（ N、R）（ P 〈 0. 05）. After the modeling,the pain threshold of the group S and SR were lower than group N（ P 〈 0. 05）,and there was no significant difference between the group R and N. 2） Fecal score： The fecal scores of group S,R,SR were significantly higher than the group N（ P 〈 0. 05）,the fecal score of group SR was significantly higher than the group S and R（ P 〈 0. 05）. 3） Open field test： Before the restraint stress,the horizontal motion of the group S and SR tend to decrease compared to the group N、R,while the vertical m