摘要
目的:探讨便秘型肠易激综合征(C-IBS)大鼠模型对直肠球囊扩张的内脏敏感性改变和脊髓背角5-羟色胺(5-HT)、c-fos的分布和异常表达.方法:C-IBS大鼠模型组应用冰水ig方法建立(A组,n=10),和正常对照大鼠(B组,n=10).所有大鼠给予直肠内球囊扩张,检测球囊扩张引起腹部收缩反射的最小容量阈值及球囊不同容量扩张时腹部收缩反射的次数.腰骶段脊髓背角5-HT和c-fos表达应用免疫组织化学染色及计算机图像分析系统半定量进行分析.结果:直肠内球囊扩张时,A组引起腹部收缩的最小容量阈值略高于B组,无明显统计学差并(0.59±0.09 vs 0.57±0.13,P>0.05).直肠球囊扩张体积1.0mL时A组腹部收缩反射次数低于B组(10.3±3.3 vs 18.3±5.5,P<0.05);体积1.5和2.0mL高容量扩张时两组无明显差异(P>0.05).A组腰骶段脊髓背角5-HT、c-fos阳性神经组织的面积均明显高于B组(5-HT面积:146.5±15.1 vs 109.3±18.5;5-HT OD:45826±2563.2 vs 29358±8965.5:c-fos面积:125.4±23.3 vs 88.7±23.2;c-fos OD:46258±4642 vs 33238±4587;均P<0.05).结论:C-IBS大鼠模型存在对直肠球囊扩张的内脏敏感性异常,脊髓背角5-HT、c-fos的异常表达可能参与C-IBS大鼠内脏敏感性异常的调节.
AIM： To study the visceral sensitivity by rectal balloon distension and expression of 5-hydroxy-tryptamine （5-HT） and c-fos in the spinal dorsal horn of a rat model with constipation-predominant irritable bowel syndrome （C-IBS）. METHODS： The rat model was established by intragastric injection with ice-cold water （0-4℃）. The perception thresholds and the number of abdominal withdrawal reflexes （AWRs） were recorded during rectal balloon distention in order to evaluate visceral sensitivity in the model group （A, n = 10） and control group （B, n = 10）. Expression of 5-HT and c-fos in the spinal dorsal horn was shown by immunohistochemical staining, and analyzed semi-quantitatively by computerized color image analyzer using immunoreactive areas and optical density （OD）. The statistical difference of the OD and immunoreactive areas between the two groups was examined by t test. RESULTS： The perception threshold in group A was slightly higher than that in group B during rectal balloon distention, but there was no significant difference （0.59 ± 0.09 vs 0.57 ± 0.13, P 〉 0.05）. The number of AWRs to the lower balloon content （1.0 mL） was much lower in group A than in group B （10.3 ± 3.3 vs 18.3 ± 5.5, P 〈 0.05）, although no difference was found to the higher balloon content （1.5 and 2.0 mL）. Immunoreactive area and OD of 5-HT- and c-fos-positive neurons and fibers in group A were significantly higher than those in group B （5-HT immunoreactive area, 146.5 ± 15.1 vs 109.3 ± 18.5; 5-HT OD, 45826 ± 2563.2 vs 29358 ± 8965.5; c-fos immunoreactive area, 125.4 ± 23.3 vs 88.7 ± 23.2; c-fos OD, 46258 ± 4642 vs 33238 ± 4587; all P 〈 0.05）. CONCLUSION： The model of C-IBS has a decreased visceral sensitivity to rectal balloon distention. The increased expression of 5-HT and c-fos in the spinal dorsal horn is probably involved in the process.
出处
《世界华人消化杂志》
CAS
北大核心
2007年第25期2718-2722,共5页
World Chinese Journal of Digestology
