目的探讨P2X7特异性受体拮抗剂A438079对肠易激综合征(irritable bowel syndrome,IBS)致内脏高敏感化大鼠在结肠扩张刺激状态时,骶髓后联合核(dorsal commissural nucleus,DCN)中P2X7、OX42、IL-1β、P38及脊髓背角中CGRP表达的变化,为探讨IBS内脏敏化的神经机制提供理论依据。方法以15只旋毛虫感染大鼠建立肠易激综合征模型,随机分为三组,总共分为:B.IBS大鼠结肠扩张刺激组(n=5)、C.IBS大鼠鞘内注射0.9%生理盐水后结肠扩张刺激组(n=5)、D.IBS大鼠鞘内注射A438079后结肠扩张刺组(n=5)。另外以5只正常大鼠作正常大鼠结肠扩张刺激组(n=5)、。采用免疫荧光组织化学方法观察大鼠DCN中P2X7、OX42、IL-1β、P38及脊髓后角中CGRP表达变化。结果与B组IBS扩张刺激组相比较,D组鞘内注射拮抗剂A438079后在结肠扩张刺激时IBS大鼠DCN核团中P2X7、OX42、IL-1β、P38及骶髓后角中CGRP的表达量均明显下降(P〈0.01)。结论 P2X7受体在IBS致内脏敏化过程中广泛参与,并可能起重要作用。
Objective To explore the effect of A438079,a P2X7 receptor antagonist,on expression of P2X7,Ox42,IL-1β,P38 in dorsal commissural nucleus and calcitonin gene related peptide(CGRP) in dorsal horn of sacral segment of spinal cord in rats with irritable bowel syndrome(IBS) induced by the stimulation of colorectal distention,and to provide a theoretical evidence in the prevention and treatment of IBS. Methods Fifteen rats were gavaged with the Trichinella spiralis to establish the IBS model,and then were divided into three groups: IBS+colon distension group(B),IBS+colon distension+intrathecal injection of saline(C),and IBS+colon distension+intrathecal injection of A438079(D).Five normal rats with colon distension were chosen as control group.Immunofluorescent staining method was used to observe the expression of P2X7,OX42,I L-1β,P38 in neurons of DCN and CGRP expression in dorsal horn of the sacral segment of spinal cord in rats. Results The expression of P2X7,OX42,IL-1β,P38 and CGRP in IBS+colon distension+A438079 group were all significantly lower than those in IBS+colon distension group(P0.01). Conclusion P2X7 receptor may be involved in the development of IBS-induced visceral hyperalgesia.