Intest Res.  2010 Dec;8(2):162-171. 10.5217/ir.2010.8.2.162.

The Effect of Autonomic Nerve System on Neurotensin Induced Motility in Isolated, Vascularly Perfused Rat Colon

• Ji JH
• Kim SM
• Seo E
• Cho YS
• Yoo SH
• Han JH
• Chae HB
• Park SM
• Youn SJ

• KMID: 2284934
• DOI: http://doi.org/10.5217/ir.2010.8.2.162

Abstract

BACKGROUND/AIMS
Although neurotensin (NT) stimulates colon motility and the passage of intestinal contents, the associated mechanism of action remains unclear. The objective of this study was to investigate the effects of NT on colon motility using isolated rat colon.
METHODS
Intraluminal pressure was measured at both the proximal and distal portions of the isolated colon. An isolated rat colon was perfused with Krebs solution via the superior mesenteric artery. After stabilization, NT was administered in concentrations of 14, 28, 138 and 276 pM. After pretreatment with phentolamine, propranolol, hexamethonium, atropine or tetrodotoxin, NT was administered at a concentration of 276 pM, and then the intraluminal pressure was monitored.
RESULTS
NT significantly increased colon motility at concentrations of 14, 28, 138, and 276 in the proximal colon (25.1+/-6.5%, 175.4+/-117.0%, 240.8+/-115.1% and 252.3+/-110.6%, respectively) and in the distal colon (35.6+/-11.8%, 97.5+/-35.1%, 132.7+/-36.7% and 212.1+/-75.2%, respectively). The stimulant effect of NT was more potent in the proximal colon, in a concentration-dependent manner (P<0.05). The stimulant effect of NT was significantly inhibited by atropine at both the proximal and distal colon and by tetrodotoxin at the proximal colon, but not by tetrodotoxin at the distal colon and not by propranolol, phentolamine, or hexamethonium at both the proximal and distal colon.
CONCLUSIONS
NT increased colon motility at both the proximal and distal portions of the rat colon. The effects were more prominent at the proximal portion. The results of this study suggest that the stimulant action of NT may be mediated by local cholinergic muscarinic receptors.

Keyword

Neurotensin (NT); Colon Motility; Cholinergic

MeSH Terms

Animals
Atropine
Autonomic Pathways
Colon
Gastrointestinal Contents
Hexamethonium
Isotonic Solutions
Mesenteric Artery, Superior
Neurotensin
Phentolamine
Propranolol
Rats
Receptors, Muscarinic
Tetrodotoxin
Atropine
Hexamethonium
Isotonic Solutions
Neurotensin
Phentolamine
Propranolol
Receptors, Muscarinic
Tetrodotoxin