Medulla OblongataPiloerectionBrain StemLateral Medullary SyndromeThermoreceptorsForamen MagnumKidney MedullaProlactin-Releasing HormoneReticulumSpinal CordBrainAutonomic PathwaysSolitary NucleusHypothalamusRespirationReticular FormationCerebellumMagnetic Resonance ImagingChemoreceptor CellsVagus NerveCatsSudden Infant DeathGerminomaNeuronsRats, Inbred StrainsPressoreceptorsScrapieRats, Sprague-DawleyBrain ChemistryCatecholaminesProto-Oncogene Proteins c-fosBlood PressureImmunohistochemistryAneurysm, RupturedNorepinephrineSympathetic Nervous SystemPonsRats, Inbred WKYCentral Nervous SystemNeural PathwaysRats, WistarSerotoninCarbon DioxideRats, Inbred SHRHeart RateSheepBrain NeoplasmsTissue DistributionRNA, MessengerTime Factors