Enteric Nervous SystemNeurogliaCell DifferentiationHirschsprung DiseaseMyenteric PlexusSubmucous PlexusCell ProliferationCentral Nervous SystemNeural CrestNervous SystemNeuronsProto-Oncogene Proteins c-retGastrointestinal TractCells, CulturedGastrointestinal MotilityPeripheral Nervous SystemImmunohistochemistryGlial Cell Line-Derived Neurotrophic Factor ReceptorsDigestive SystemSOXE Transcription FactorsStem CellsSignal TransductionGene Expression Regulation, DevelopmentalGlial Cell Line-Derived Neurotrophic FactorEndothelin-3Cell MovementRNA, MessengerMice, Inbred C57BLNerve Tissue ProteinsMice, TransgenicIntestinesGangliaTranscription FactorsCell DivisionQuailColonMice, KnockoutNerve Growth FactorsIn Situ HybridizationBrainCell LineageCell LineReverse Transcriptase Polymerase Chain ReactionNeurogenesisMolecular Sequence DataChick EmbryoCell CountIleumGene Expression RegulationTime FactorsReceptor Protein-Tyrosine KinasesRats, Sprague-DawleyGene ExpressionPhenotypeBlotting, WesternIntestine, SmallVasoactive Intestinal PeptideApoptosisAstrocytesCentral Nervous System DiseasesDrosophila ProteinsDigestive System Physiological PhenomenaMutationEmbryo, MammalianMegacolonNeurofilament ProteinsHomeodomain ProteinsAnimals, NewbornSerotonin 5-HT4 Receptor AgonistsDisease Models, AnimalProto-Oncogene ProteinsHigh Mobility Group ProteinsGuinea PigsCell SurvivalPeristalsisMice, Mutant StrainsOligodendrogliaBase SequenceVagus NerveCell CycleInterstitial Cells of CajalDNA-Binding ProteinsCell Line, TumorZebrafishIntestinal Pseudo-ObstructionNeurturinGlial Fibrillary Acidic ProteinBromodeoxyuridineCoturnixJejunumNeuropeptidesEmbryo, NonmammalianTumor Cells, CulturedEmbryonic Stem CellsMorphogenesisIntestinal MucosaDose-Response Relationship, DrugRetinaTransfectionFlow Cytometry