Tuyển tập các báo cáo nghiên cứu khoa học quốc tế về bệnh thú y đề tài: Experimental peritonitis induced by oral administration of indomethacin in Mongolian gerbils | J. Vet. Set. 2006 7 2 143-150 JOURNAL OF Veterinary Science Alteration of nitrergic neuromuscular transmission as a result of acute experimental colitis in rat Tae-Sik Sung1 Jun-Ho La1 Tae-Wan Kim2 Il-Suk Yang1 1 Department of Physiology College of Veterinary Medicine Seoul National University Seoul 151-742 Korea department of Physiology College of Veterinary Medicine Kyungpook National University Daegu 702-701 Korea Nitric oxide NO is a non-adrenergic non-cholinergic neurotransmitter found in the enteric nervous system that plays a role in a variety of enteropathies including inflammatory bowel disease. Alteration of nitrergic neurons has been reported to be dependent on the manner by which inflammation is caused. However this observed alteration has not been reported with acetic acid-induced colitis. Therefore the purpose of the current study was to investigate changes in nitrergic neuromuscular transmission in experimental colitis in a rat model. Distal colitis was induced by intracolonic administration of 4 acetic acid in the rat. Animals were sacrificed at 4 h and 48 h post-acetic acid treatment. Myeloperoxidase activity was significantly increased in the acetic acid-treated groups. However the response to 60 mM KC1 was not significantly different in the three groups studied. The amplitude of phasic contractions was increased by N -nitro-L-arginine methyl ester L-NAME in the normal control group but not in the acetic acid-treated groups. Spontaneous contractions disappeared during electrical field stimulation EFS in normal group. However for the colitis groups these contractions initially disappeared and then reappeared during EFS. Moreover the observed disappearance was diminished by L-NAME this suggests that these responses were NO-mediated. In addition the number of NADPH-diaphorase positive nerve cell bodies in the myenteric plexus was not altered in the distal colon whereas the area of NADPH-diaphorase positive fibers in the circular muscle layer was .
