title: Establishment of a protocol for determining gastrointestinal transit time in mice using barium and radiopaque markers.
abstract: OBJECTIVE
  The purpose of this study was to establish a minimally invasive and reproducible protocol for estimating the gastrointestinal (GI) transit time in mice using barium and radiopaque markers.
  
  
  METHODS
  Twenty 5- to 6-week-old Balb/C female mice weighing 19-21 g were used. The animals were divided into three groups: two groups that received loperamide and a control group. The control group (n = 10) animals were administered physiological saline (1.5 mL/kg) orally. The loperamide group I (n = 10) and group II (n = 10) animals were administered 5 mg/kg and 10 mg/kg loperamide orally, respectively. Thirty minutes after receiving the saline or loperamide, the mice was administered 80 µL of barium solution and six iron balls (0.5 mm) via the mouth and the upper esophagus by gavage, respectively. Afterwards, the mice were continuously monitored with fluoroscopic imaging in order to evaluate the swallowing of the barium solution and markers. Serial fluoroscopic images were obtained at 5- or 10-min intervals until all markers had been excreted from the anal canal. For analysis, the GI transit times were subdivided into intestinal transit times (ITTs) and colon transit times (CTTs).
  
  
  RESULTS
  The mean ITT was significantly longer in the loperamide groups than in the control group (p < 0.05). The mean ITT in loperamide group II (174.5 ± 32.3) was significantly longer than in loperamide group I (133.2 ± 24.2 minute) (p < 0.05). The mean CTT was significantly longer in loperamide group II than in the control group (p < 0.05). Also, no animal succumbed to death after the experimental procedure.
  
  
  CONCLUSIONS
  The protocol for our study using radiopaque markers and barium is reproducible and minimally invasive in determining the GI transit time of the mouse model.
authors: Department of Radiology, Chonnam National University Hwasun Hospital, Chonnam National University Medical School, Hwasun 519-763, Korea.
authors: Bolormaa
authors: B
authors: Myagmarjalbuu
authors: Myeong Ju
authors: MJ
authors: Moon
authors: Suk Hee
authors: SH
authors: Heo
authors: Seo In
authors: SI
authors: Jeong
authors: Jong-Seong
authors: JS
authors: Park
authors: Jae Yeoul
authors: JY
authors: Jun
authors: Yong Yeon
authors: YY
authors: Jeong
authors: Heoung Keun
authors: HK
authors: Kang
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001466:Barium Sulfate / Q000494:pharmacology; D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D005471:Fluoroscopy; D005772:Gastrointestinal Transit / Q000502:physiology*; D007501:Iron; D008139:Loperamide / Q000008:administration & dosage; D051379:Mice; D008807:Mice, Inbred BALB C; D008855:Microscopy, Electron, Scanning; D019736:Prostheses and Implants; D015203:Reproducibility of Results; D012965:Sodium Chloride / Q000008:administration & dosage; D013499:Surface Properties
chemical_list: D003287:Contrast Media; D001466:Barium Sulfate; D012965:Sodium Chloride; D008139:Loperamide; D007501:Iron
keywords: Experimental study; Fluoroscopy; Gastrointestinal; Loperamide; Motility disorder