title: Disturbed pyloric motility in Ws/Ws mutant rats due to deficiency of c-kit-expressing interstitial cells of Cajal.
abstract: Interstitial cells of Cajal (ICC) are believed to initiate the basic contractile activity of the gastrointestinal tract. Interstitial cells of Cajal express c-kit receptor tyrosine kinase and are deficient in Ws/Ws mutant rats with a small deletion of the c-kit gene. As Ws/Ws rats show remarkable bile reflux to the stomach, the contraction pressure of the pylorus was compared between Ws/Ws and control +/+ rats. The contraction pressure of the pylorus was measured using a microtransducer, which was inserted through a pin-hole in the anterior wall of the stomach under anesthesia. The magnitude of bile reflux was estimated by measuring the content of bile acids in the stomach. The c-kit messenger RNA-expressing cells were detected by in situ hybridization. Frequency and the maximum pressure of the contraction were comparable between Ws/Ws and +/+ rats, but the duration of the contraction was significantly shorter in Ws/Ws rats than in +/+ rats. The number of c-kit messenger RNA-expressing ICC in the pylorus of Ws/Ws rats was 1.7% that of +/+ rats. The bile reflux observed in Ws/Ws rats was attributed to the decrease in the duration of the pyloric contraction, which appeared to result from the deficiency of c-kit messenger RNA-expressing ICC.
authors.affiliation: Department of Pathology, Osaka University Medical School, Suita, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Nakama
authors.forename: S
authors.initials: S
authors.lastname: Hirota
authors.forename: T
authors.initials: T
authors.lastname: Okazaki
authors.forename: K
authors.initials: K
authors.lastname: Nagano
authors.forename: S
authors.initials: S
authors.lastname: Kawano
authors.forename: M
authors.initials: M
authors.lastname: Hori
authors.forename: Y
authors.initials: Y
authors.lastname: Kitamura
mesh_terms: D000821:Animal Feed; D000818:Animals; D001647:Bile Acids and Salts / Q000032:analysis; D011312:Pressure; D019009:Proto-Oncogene Proteins c-kit / Q000096:biosynthesis* / Q000235:genetics; D011708:Pylorus / Q000378:metabolism* / Q000502:physiology*; D051381:Rats; D011922:Rats, Mutant Strains; D013270:Stomach / Q000737:chemistry
chemical_list: D001647:Bile Acids and Salts; D019009:Proto-Oncogene Proteins c-kit