内脏高敏感状态下食管酸灌注诱导的鼠脊髓背角c-Fos基因表达的研究  

c-Fos expression evoked by esophageal acid perfusion in spinal dorsal horn in ovalbumin sensitized rats

作　　者：杨敏[1] 房殿春[2] 胡志安[3] 陈东风[1] 赵帮云 

机构地区：[1]第三军医大学大坪医院消化内科,重庆400042 [2]第三军医大学西南医院消化内科,重庆400038 [3]第三军医大学基础部生理教研室,重庆400038

出　　处：《重庆医学》2007年第15期1508-1510,共3页Chongqing medicine

摘　　要：目的观察在内脏高敏感状态下,食管酸灌注诱导的大鼠脊髓背角Fos蛋白表达的表达,初步探索食管内脏感觉过敏在脊髓水平敏感化的分子机制。方法采用腹腔注射鸡卵清蛋白基础致敏联合食管酸灌注的方法,建立内脏高敏感性-食管化学刺激大鼠模型;采用免疫组织化学方法和显微图像分析技术研究,在生理条件、内脏高敏感状态下进行食管酸灌注时Fos蛋白激活模式的差异。结果模型组大鼠双侧脊髓背角内有大量的Fos样免疫反应(FLI)阳性神经元,集中分布于背角Ⅰ～Ⅱ、Ⅴ～Ⅶ层,其FLI阳性神经元数量和平均光密度值较单纯食管酸灌注组和单纯,OVA(ovalbumin)致敏组明显增加,差异有统计学意义(P<0.05)。单纯酸灌注组和单纯OVA致敏组在背角Ⅰ～Ⅱ、Ⅴ～Ⅵ、Ⅹ层的FLI阳性神经元数量均较生理盐水对照组显著增加,差异有统计学意义(P<0.01)。单纯酸灌注组在背角Ⅰ～Ⅱ层和Ⅲ～Ⅳ层FLI阳性细胞数较单纯OVA致敏组显著增加,差异有统计学意义(P<0.05)。结论腹腔注射鸡卵清蛋白基础致敏,对食管酸灌注诱导的脊髓背角内Fos蛋白表达有活化作用,c-Fos过度表达的阳性神经元的兴奋性增加和神经可塑性改变,促进了内脏高敏感性在脊髓水平敏感化的形成和维持。Objective To investigate the characteristics of c-Fos expression evoked by esophageal acid perfusion in spinal dorsal horn in ovalbumin sensitized rats, and to map the contribution of specific brain areas to sensitized responsivity and to emphasize the coding change of cortical processing. Methods The rat model of esophageal visceral hypersensitivity was established by the basic ovalbumin-sensitization combined with intra-esophageal mucosal acid exposure. The neuronal expressions of c-Fos proto-oncogene were detected with immunohistochemical counter-staining and computerized color image analyzer. Results The Fos-IR neurons were abundantly concentrated superficial layers Ⅰ - Ⅱ and Ⅴ-Ⅶ of spinal dorsal horns neurons. The numbers and mean OD values of Fos-IR positive neurons in model group by established basic ovalbumin-sensitised plus esophageal acid perfusion were significantly stronger, compared with other groups （all P〈0.05）. Fos-IR neurons with esophageal acid perfusion and ovalbumin-sensitised group were larger than that of esophageal saline perfusion in layers Ⅰ -Ⅱ , Ⅴ-Ⅶ and X of spinal dorsal horns（P〈0.01）. Fos-IR neurons following acid exposure was larger than that of only ovalbumin-sensitised group in layers Ⅰ- Ⅱ and Ⅲ-Ⅳof spinal dorsal horns （P〈0.05）. Conclusion The basic ovalbumin-sensitization facilitates dramatically the c-Fos expression evoked by esophageal acid perfusion, and enhances the quantity and intensity in spinal dorsal horn, suggesting that visceral hypersensitivity induced by ovalbumin may alter reactivity processing of esophageal acid stimulation in spinal areas and that the dysfunction of visceral central neurons or alterations may produce and mediate esophageal hypersensitivity.

关 键 词：内脏高敏感性 c—Fos 免疫组织化学 食管酸灌注 卵清蛋白 脊髓背角 

分 类 号：R363[医药卫生—病理学]