Raphe NucleiSerotoninPeptostreptococcusSerotonergic NeuronsBrain StemPeptococcusThermoreceptorsPeriaqueductal GrayReticular FormationMedulla OblongataNeuronsPhysical StimulationEnkephalin, Ala(2)-MePhe(4)-Gly(5)-Tryptophan HydroxylasePeriapical AbscessMorphineRats, Sprague-DawleyAfferent PathwaysMicroinjectionsPainReceptors, SerotoninSerotonin AgentsSuppuration8-Hydroxy-2-(di-n-propylamino)tetralinSpinal CordSerotonin Receptor AgonistsHot TemperatureReceptor, Serotonin, 5-HT1ASerotonin AntagonistsAnalgesics, OpioidElectric StimulationReceptors, Serotonin, 5-HT1Action Potentials5,7-DihydroxytryptamineSerotonin Plasma Membrane Transport ProteinsSexologyPsychoanalysisSerotonin Uptake InhibitorsHydroxyindoleacetic AcidReceptor, Serotonin, 5-HT2AMethysergideBacteria, AnaerobicSerotonin 5-HT1 Receptor AgonistsReceptors, Serotonin, 5-HT2Fenclonine