Peripheral corticotropin releasing hormone mediates post-inflammatory visceral hypersensitivity in rats.

Abstract

AIM:

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.

METHODS:

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.

RESULTS:

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.

CONCLUSION:

These results suggest that increased peripheral CRH mediates the enhanced visceral nociception in rats recovered from experimental colitis.

• Authors: Jun-Ho La, Tae-Sik Sung, Hyun-Ju Kim, Tae-Wan Kim, Tong-Mook Kang, Il-Suk Yang
• Journal: World journal of gastroenterology (World J Gastroenterol) Vol. 14 Issue 5 Pg. 731-6 (Feb 07 2008) ISSN: 1007-9327 [Print] United States
• PMID: 18205263 (Publication Type: Journal Article)

Chemical References

• Corticotropin-Releasing Hormone

Topics

• Abdominal Pain (etiology, immunology)
• Animals
• Catheterization
• Colitis (complications, immunology)
• Colon (immunology, innervation)
• Corticotropin-Releasing Hormone (blood, immunology)
• Disease Models, Animal
• Male
• Nociceptors (immunology)
• Rats
• Rats, Sprague-Dawley