title: The effect of urocortin 1 on motility in isolated, vascularly perfused rat colon.
abstract: OBJECTIVE
  Urocortin 1, a corticotropin-releasing factor related peptide, increases colonic motility under stressful conditions. We investigated the effect of urocortin 1 on colonic motility using an experimental model with isolated rat colon in which the blood flow and intestinal nerves were preserved. Furthermore, we assessed whether this effect was mediated by adrenergic or cholinergic nerves.
  
  
  METHODS
  Colonic motility was measured in the proximal and distal parts of resected rat colon. The colon resected from the peritoneum was stabilized, and then urocortin 1 (13.8, 138, 277, and 1,388 pM) was administered via a blood vessel. Motility index was measured in the last 5 min of the 15 min administration of urocortin 1 and expressed as percentage change from baseline. Subsequently, the change in motility was measured by perfusing urocortin 1 in colons pretreated with phentolamine, propranolol, hexamethonium, atropine, or tetrodotoxin.
  
  
  RESULTS
  At concentrations of 13.8, 138, 277, and 1,388 pM, urocortin 1 increased the motility of proximal colon (20.4 ± 7.2%,48.4 ± 20.9%, 67.0 ± 25.8%, and 64.2 ± 20.9%, respectively) and the motility of distal colon (3.3 ± 3.3%, 7.8 ± 7.8%, 71.1 ± 28.6%,and 87.4 ± 32.5%, respectively). The motility induced by urocortin 1 was significantly decreased by atropine to 2.4 ± 2.4% in proximal colon and 3.4 ± 3.4% in distal colon (p < 0.05). However, tetrodotoxin, propranolol, phentolamine, and hexamethonium did not inhibit motility.
  
  
  CONCLUSIONS
  Urocortin 1 increased colonic motility and it is considered that this effect was directly mediated by local muscarinic cholinergic receptors.
authors.affiliation: Department of Internal Medicine, Chungbuk National University College of Medicine, Cheongju, Korea.
authors.forename: Il Young
authors.initials: IY
authors.lastname: You
authors.affiliation: Department of Internal Medicine, Chungbuk National University College of Medicine, Cheongju, Korea.
authors.forename: Seungho
authors.initials: S
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Chungbuk National University College of Medicine, Cheongju, Korea.
authors.forename: Ki Bae
authors.initials: KB
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Chungbuk National University College of Medicine, Cheongju, Korea.
authors.forename: Hee Seung
authors.initials: HS
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Chungbuk National University College of Medicine, Cheongju, Korea.
authors.forename: Jong Soon
authors.initials: JS
authors.lastname: Jang
authors.affiliation: Department of Internal Medicine, Chungbuk National University College of Medicine, Cheongju, Korea.
authors.forename: Myeongho
authors.initials: M
authors.lastname: Yeon
authors.affiliation: Department of Internal Medicine, Chungbuk National University College of Medicine, Cheongju, Korea.
authors.forename: Joung-Ho
authors.initials: JH
authors.lastname: Han
authors.affiliation: Department of Internal Medicine, Chungbuk National University College of Medicine, Cheongju, Korea.
authors.forename: Soon Man
authors.initials: SM
authors.lastname: Yoon
authors.affiliation: Department of Internal Medicine, Chungbuk National University College of Medicine, Cheongju, Korea.
authors.forename: Hee Bok
authors.initials: HB
authors.lastname: Chae
authors.affiliation: Department of Internal Medicine, Chungbuk National University College of Medicine, Cheongju, Korea.
authors.forename: Seon Mee
authors.initials: SM
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Chungbuk National University College of Medicine, Cheongju, Korea.
authors.forename: Sei Jin
authors.initials: SJ
authors.lastname: Youn
mesh_terms: D000818:Animals; D003106:Colon / Q000187:drug effects* / Q000502:physiology; D007275:Injections, Intravenous; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D018377:Neurotransmitter Agents / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D011950:Receptors, Cholinergic / Q000737:chemistry / Q000378:metabolism; D054832:Urocortins / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D018377:Neurotransmitter Agents; D011950:Receptors, Cholinergic; D054832:Urocortins
keywords: Cholinergic receptors; Corticotropin-releasing factor; Muscarinic receptors; Rats; Urocortins