Enteric Nervous SystemEpithelial CellsNeurogliaHirschsprung DiseaseMyenteric PlexusSubmucous PlexusCentral Nervous SystemNeural CrestNervous SystemProto-Oncogene Proteins c-retGastrointestinal TractNeuronsGastrointestinal MotilityPeripheral Nervous SystemDigestive SystemGlial Cell Line-Derived Neurotrophic Factor ReceptorsSOXE Transcription FactorsGlial Cell Line-Derived Neurotrophic FactorEndothelin-3ImmunohistochemistryIntestinesCells, CulturedColonEpitheliumGangliaCell MovementIleumIntestinal MucosaQuailCell DifferentiationIntestine, SmallNerve Tissue ProteinsNerve Growth FactorsBrainStem CellsRNA, MessengerGene Expression Regulation, DevelopmentalVasoactive Intestinal PeptideCell LineCentral Nervous System DiseasesDigestive System Physiological PhenomenaSignal TransductionIn Situ HybridizationMice, TransgenicMegacolonMice, Inbred C57BLSerotonin 5-HT4 Receptor AgonistsReceptor Protein-Tyrosine KinasesGuinea PigsPeristalsisNeurofilament ProteinsRats, Sprague-DawleyChick EmbryoVagus NerveInterstitial Cells of CajalCell CountAstrocytesJejunumDrosophila ProteinsIntestinal Pseudo-ObstructionNeurturinNeurogenesisHigh Mobility Group ProteinsMice, KnockoutDisease Models, AnimalReverse Transcriptase Polymerase Chain ReactionMolecular Sequence DataTime FactorsIntestine, LargeRespiratory MucosaCell ProliferationBlotting, WesternAnimals, NewbornNeurotransmitter AgentsGene ExpressionIleusMutationCeliac PlexusNeuropeptidesNitrergic NeuronsUbiquitin ThiolesteraseCoturnixCentral Nervous System NeoplasmsGlial Fibrillary Acidic ProteinTranscription FactorsMice, Mutant StrainsStomachManducaReceptors, Serotonin, 5-HT4OligodendrogliaRetinaMicroscopy, ConfocalPhenotypeBronchiAxonsCell LineageCholine O-AcetyltransferaseProto-Oncogene ProteinsTetrodotoxinZebrafish