Interstitial cells of Cajal in the gastrointestinal musculature of W mutant mice.
Interstitial cells of Cajal (ICC) are important regulatory cells generating electrical rhythmicity and transducing neural signals in the gastrointestinal musculature. ICC express the proto-oncogene c-kit, a receptor tyrosine kinase, and can be examined morphologically using the c-Kit antibody. The c-kit gene is allelic with the murine white-spotting locus W, and the c-kit mutation (W mutation) affects various aspects of hematopoietic cells, germ cells, melanocytes, mast cells, and ICC. Heterozygous W/W( v) mutant mice lack a specific type of ICC and have been used to reveal its function. To search for a new model that lacks a specific type of ICC, we examined homozygous W( v)/W( v) black-eyed-white mice that are viable with anemia. Results showed the principal patterns of ICC deficiency were the same between the W/W( v) and W( v)/W( v) mutants. In the stomach of both mice, intramuscular ICC (ICC-IM) were missing and myenteric ICC (ICC-MY) were reduced in number. In the small intestine, the number of ICC-MY was severely reduced in spite of a normal distribution of deep muscular plexus ICC (ICC-DMP). The cecum also exhibited fewer reduced. ICC-IM in the colon were almost entirely missing, whereas ICC-MY were reduced only in the distal colon. In the small intestine and colon, the number of remaining ICC-MY in W( v)/W( v) mice was greater than that in W/W( v) mice. The enteric nervous system of the two mutant mice showed normal characteristics. From these findings, we conclude that W( v)/W( v) mice represent a new genotype that lacks a part of the ICC in its gastrointestinal musculature.
Iino
Satoshi
S
Department of Morphological and Physiological Sciences, University of Fukui Faculty of Medical Sciences, Fukui, Japan. iinosa@u-fukui.ac.jp
Horiguchi
Satomi
S
Horiguchi
Kazuhide
K
Nojyo
Yoshiaki
Y
D000818:Animals; D041981:Gastrointestinal Tract / Q000166:cytology* / Q000294:innervation / Q000378:metabolism* / Q000473:pathology; D005786:Gene Expression Regulation; D051379:Mice; D008817:Mice, Mutant Strains; D009130:Muscle, Smooth / Q000166:cytology* / Q000294:innervation / Q000473:pathology; D009154:Mutation / Q000235:genetics*; D019009:Proto-Oncogene Proteins c-kit / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D012680:Sensitivity and Specificity
D012333:RNA, Messenger; D019009:Proto-Oncogene Proteins c-kit