HyperalgesiaReceptors, Opioid, muAnalgesics, OpioidReceptors, OpioidReceptors, Opioid, deltaReceptors, Opioid, kappaOpioid PeptidesPain ThresholdPain MeasurementPainNarcotic AntagonistsNociceptorsNaloxoneAnalgesicsCarrageenanMorphineInjections, SpinalRats, Sprague-DawleyNaltrexoneOpioid-Related DisordersPhysical StimulationCapsaicinFreund's AdjuvantEnkephalin, Ala(2)-MePhe(4)-Gly(5)-Hot TemperatureEnkephalinsSpinal CordNeuralgiaDynorphinsNarcoticsDrug ToleranceGanglia, SpinalTRPV Cation ChannelsEndorphinsBuprenorphineEnkephalin, D-Penicillamine (2,5)-AnalgesiaPosterior Horn CellsTouchBehavior, AnimalDose-Response Relationship, DrugSciatic NeuropathyFentanylEnkephalin, LeucineHyperesthesiaMustard PlantNociceptionDisease Models, AnimalAnalgesics, Non-NarcoticEnkephalin, Leucine-2-AlanineInflammationSpinal NervesChronic PainSensory Receptor CellsDiprenorphinePain, ReferredCyclohexanecarboxylic Acidsbeta-EndorphinSubstance Withdrawal SyndromeRats, WistarSciatic NerveMethadoneBenzeneacetamidesFootVisceral PainNerve Fibers, UnmyelinatedNeurons, AfferentPain, PostoperativePiperidinesEdemaPeripheral Nervous System DiseasesReceptors, Neurokinin-1MorphinansReflex, AbdominalHindlimbPyrrolidinesReceptors, N-Methyl-D-AspartateKetamineSubstance PVisceral AfferentsFormaldehydeSensory System AgentsMedulla OblongataHydromorphoneMorphine DerivativesNeurokinin-1 Receptor AntagonistsPain, IntractableVisceraInjections, IntradermalElectroacupunctureDrug InteractionsMononeuropathiesNerve Growth FactorBenzomorphansDinoprostoneHeroinPeriaqueductal GrayTime FactorsTrigeminal Caudal NucleusAmines