La Jun-Ho, Sung Tae-Sik, Kim Hyun-Ju, Kim Tae-Wan, Kang Tong-Mook, Yang Il-Suk
Department of Physiology, College of Veterinary Medicine, Seoul National University, San 56-1 Sillim-Dong, Kwanak-Gu, Seoul 151-742, Republic of Korea.
World J Gastroenterol. 2008 Feb 7;14(5):731-6. doi: 10.3748/wjg.14.731.
To investigate whether peripheral corticotropin releasing hormone (CRH), which is up-regulated in intestinal inflammation, mediates the post-inflammatory visceral hypersensitivity in a rat model of colitis.
We measured mucosal myeloperoxidase (MPO) activity as a marker of inflammation, plasma CRH level, and abdominal withdrawal reflex (AWR) to colorectal distension as a visceral nociceptive response at 2, 7 and 14 d after the induction of colitis with 4% acetic acid.
Colonic inflammation, quantified by MPO activity, significantly increased on d 2 and subsided thereafter, which indicated a resolution of inflammation within 7 d. On the contrary, plasma CRH level and AWR score were increased on d 2, remained high on d 7, and returned to control level on d 14. Intraperitoneal injection of a CRH antagonist, astressin (30 mug/kg), significantly attenuated the post-inflammatory visceral hypersensitivity on d 7. Furthermore, intraperitoneal administration of CRH (3 and 10 mug/kg) mimicked the post-inflammatory visceral hypersensitivity in naive rats.
These results suggest that increased peripheral CRH mediates the enhanced visceral nociception in rats recovered from experimental colitis.
研究在肠道炎症中上调的外周促肾上腺皮质激素释放激素（CRH）是否介导结肠炎大鼠模型炎症后的内脏超敏反应。
我们以黏膜髓过氧化物酶（MPO）活性作为炎症标志物，测量血浆CRH水平，并在4%乙酸诱导结肠炎后的第2、7和14天，测量对结直肠扩张的腹部撤回反射（AWR）作为内脏伤害性反应。
通过MPO活性量化的结肠炎症在第2天显著增加，此后消退，这表明炎症在7天内得到缓解。相反，血浆CRH水平和AWR评分在第2天升高，在第7天保持高位，并在第14天恢复到对照水平。腹腔注射CRH拮抗剂阿斯特辛（30微克/千克）可显著减轻第7天炎症后的内脏超敏反应。此外，腹腔注射CRH（3和10微克/千克）可模拟未患过结肠炎的大鼠炎症后的内脏超敏反应。
这些结果表明，外周CRH增加介导了实验性结肠炎恢复大鼠内脏伤害感受增强。
