Differential gene expression in the murine gastric fundus lacking interstitial cells of Cajal

Background: The muscle layers of murine gastric fundus have no interstitial cells of Cajal at the level of the myenteric plexus and only possess intramuscular interstitial cells and this tissue does not generate electric slow waves. The absence of intramuscular interstitial cells in W/W-V mutants provides a unique opportunity to study the molecular changes that are associated with the loss of these intercalating cells. Method: The gene expression profile of the gastric fundus of wild type and W/W-V mice was assayed by murine microarray analysis displaying a total of 8734 elements. Queried genes from the microarray analysis were confirmed by semi-quantitative reverse transcription-polymerase chain reaction. Results: Twenty-one genes were differentially expressed in wild type and W/W-V mice. Eleven transcripts had 2.0-2.5 fold higher mRNA expression in W/W-V gastric fundus when compared to wild type tissues. Ten transcripts had 2.1-3.9 fold lower expression in W/W-V mutants in comparison with wild type animals. None of these genes have ever been implicated in any bowel motility function. Conclusions: These data provides evidence that several important genes have significantly changed in the murine fundus of W/W-V mutants that lack intramuscular interstitial cells of Cajal and have reduced enteric motor neurotransmission.