title: Reduction of gastrointestinal motility by unilateral thyroparathyroidectomy plus subdiaphragmatic vagotomy in rats.
abstract: OBJECTIVE
  To investigate whether the combined methods of unilateral thyroparathyroidectomy (TPX) and subdiaphragmatic vagotomy (VAX) can be adapted for rats and used as a reliable method to produce a rat model of long-term reduction of gastrointestinal (GI) motor function.
  
  
  METHODS
  Male Sprague-Dawley rats were randomly divided into 3 groups, normal, sham-operated and unilateral TPX plus VAX. The TPX plus VAX rats received VAX 7 d after application of TPX, and dietary intake and fecal output were then measured daily for 1 wk. After completion of the experiments, gastric emptying and small bowel transit were measured in vivo, and the contractile responses of colonic strips to excitatory and inhibitory neurotransmitters were estimated using isometric force transducers in vitro.
  
  
  RESULTS
  In comparison with normal and sham-operated rats, rats which received unilateral TPX plus VAX showed a significant decrease in body weight and in fecal pellet number and weight throughout the entire week. Application of TPX plus VAX to rats markedly delayed gastric emptying and small bowel transit. In TPX plus VAX rats, the longitudinal muscles of the proximal colon showed a significant reduction in contractile responses to acetylcholine (5 × 10(-6) mol/L), and a dramatic attenuation of contractile responses was also observed in both the longitudinal and circular muscles of the distal colon. However, the spontaneous contractility of the colonic strips from TPX plus VAX rats was not significantly affected by treatment with N-nitro-L-arginine-methyl ester (0.1 mol/L).
  
  
  CONCLUSIONS
  The results indicate that unilateral TPX plus VAX reduced the motor function of the GI tract in rats, and the reduced gut motility is likely mediated, at least in part, by inhibition of the excitatory neurotransmitter system.
authors.affiliation: Department of Pharmacology, Wonkwang University School of Medicine, Jeonbuk 570-749, South Korea.
authors.forename: Jun Ho
authors.initials: JH
authors.lastname: Lee
authors.forename: Oh Deog
authors.initials: OD
authors.lastname: Kwon
authors.forename: Seon Ho
authors.initials: SH
authors.lastname: Ahn
authors.forename: Keun Han
authors.initials: KH
authors.lastname: Choi
authors.forename: Ji Hye
authors.initials: JH
authors.lastname: Park
authors.forename: Seoul
authors.initials: S
authors.lastname: Lee
authors.forename: Bong Kyu
authors.initials: BK
authors.lastname: Choi
authors.forename: Kyu Yong
authors.initials: KY
authors.lastname: Jung
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D003106:Colon / Q000187:drug effects / Q000502:physiology; D003672:Defecation / Q000502:physiology; D003964:Diaphragm; D005746:Gastric Emptying / Q000502:physiology; D005769:Gastrointestinal Motility / Q000502:physiology*; D005772:Gastrointestinal Transit / Q000502:physiology; D008297:Male; D023421:Models, Animal; D009119:Muscle Contraction / Q000187:drug effects / Q000502:physiology; D009130:Muscle, Smooth / Q000187:drug effects / Q000502:physiology; D010280:Parathyroid Glands / Q000502:physiology / Q000601:surgery*; D016105:Parathyroidectomy / Q000379:methods*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013974:Thyroxine / Q000097:blood; D014628:Vagotomy / Q000379:methods*; D014630:Vagus Nerve / Q000502:physiology / Q000601:surgery*; D014665:Vasodilator Agents / Q000494:pharmacology
chemical_list: D014665:Vasodilator Agents; D000109:Acetylcholine; D013974:Thyroxine