为研究5-羟色胺(5-HT)增多是否通过影响肠黏膜屏障引起断奶仔鼠的腹泻,检测断奶腹泻仔鼠小肠绒毛高度(VH)、隐窝深度(CD)变化。采用21d刚断奶ICR仔鼠,分为6组,第1组为正常对照组,第2组为应激腹泻组,番泻叶(0.4kg/L)按体重15mL/kg灌胃同时后肢束缚应激处理,第3组为氢溴酸西肽普兰(CH)对照组,用CH进行腹腔注射处理,第4组CH+腹泻组,CH药物处理4h后进行应激腹泻处理;第5组对氯苯丙氨酸(PCPA)对照组,PCPA腹腔注射;第6组PCPA+应激腹泻组,PCPA药物处理4h后进行应激腹泻处理。连续处理5日后处死小鼠,取十二指肠、空肠、回肠,4%多聚甲醛固定、石蜡包埋,制作石蜡切片,HE染色,测量肠绒毛高度、隐窝深度。由HE染色结果发现,应激腹泻组、CH+应激腹泻组和PCPA+应激腹泻组与正常对照组相比,肠绒毛顶端出现充血,绒毛变短,裸露固有层等病理现象。与正常对照组相比,应激性腹泻组小鼠肠绒毛高度降低:十二指肠,空肠,回肠分别降低14.80%(P〈0.01),6.89%(P〈0.01)和19.31%(P〈0.01),隐窝深度分别升高14.09%(P〈0.01)、4.85%(P〈0.05)、11.53%(P〈0.01),故VH和CD的比值(V/C)降低:CH处理组与应激腹泻组小鼠变化趋势相同;而PCPA处理组则无明显变化。与应激腹泻小鼠相比,CH+应激腹泻组小鼠肠绒毛高度降低,尤其空肠显著降低11.18%(P〈0.01),隐窝深度升高,尤其十二指肠显著升高4.86%(P〈0.05),故V/C值也降低,而PCPA+应激腹泻组小鼠绒毛高度升高,分别为4.83%(P〈0.05),4.15%(P〈0.01),10.60%(P〈0.01),隐窝深度降低,分别为27.46%(P〈0.01)、19.21%(P〈0.01)、16.74%(P〈0.01),故V/C值升高。断奶腹泻仔鼠小肠黏膜机械屏障遭到破坏,而肠道内5-HT含量的升高也会使断奶仔鼠出现腹泻现象,同时小肠绒毛高度降低,隐窝深度增加。因此5-HT升高可能通过损伤断奶仔鼠小?
To study whether increase of 5-hydroxytryptamine(5-HT)induces weaning rat diarrhea by influencing the intestinal mucosal barrier and dectected the small intestinal villus height(VH),crypt depth(CD)of weaning diarrhea mouse.Twenty-one days old ICR weaning pups were randomly divided into six groups:the first group was control group;The second group was stress diarrhea group,which were received gavage by senna(0.4kg/L)and the dosage was 15mL/kg body weight,while their hind legs were tied during shock treatment;The third group was citalopram hydrobromide(CH)control group,which were treated with intraperitoneal injection of CH;And the fourth group was CH + stress-diarrhea group which were received stress treatment after 4hs drug treatment;The fifth was PCPA control group which were taken intraperitoneal injection with chloro-phenylalanine(PCPA);The sixth group was PCPA +stress-diarrhea group,which were treated after 4hs PCPA drug treatment.Mice were killed after 5days successive treatment,and the duodenum,jejunum,ileum were taken out,preserved in 4% paraformaldehyde,paraffin section,HE staining,then measuring intestinal villus height and crypt depth.Stress diarrhea group,CH + stress diarrhea group,and stress diarrhea PCPA + stress group appeared pathological phenomena,such as hyperemia in the top of intestinal villus,shorter villus,bare of lamina propria compared with those in control group.Compared with control group,stress diarrhea mice reduced villus height by 14.80%(P〈0.01)in duodenum,6.89%(P〈0.01)in jejunum and 19.31%(P〈0.01)in ileum,but crypt depth increased by 14.09%(P〈0.01),4.85%(P〈0.05)and 11.53%(P〈0.01),resulting in V/C ratio decrease.CH treated group was the same as in stress diarrhea group.But PCPA treatment group had no significant change.Compared with the stress diarrhea in mice,CH+stress diarrhea group reduced villus height,especially in jejunum it was significantly reduced 11.18%(P〈0.01),while crypt depth increased,especially