Injections, SpinalMorphineInfusion Pumps, ImplantableAnalgesics, OpioidSpinal CordMuscle Relaxants, CentralAnalgesicsAnesthesia, SpinalPain MeasurementHyperalgesiaBupivacainePainAnalgesia, ObstetricalSufentanilInfusions, SpinalClonidineRats, Sprague-DawleyBaclofenSpinal NervesPain, IntractableAnalgesiaAnesthetics, LocalNeostigmineSubarachnoid SpaceMuscle SpasticityFentanylPain ThresholdNeuralgiaAnesthesia, ObstetricalPruritusMeningesMeningitisMeningeal NeoplasmsDose-Response Relationship, DrugPain, PostoperativeAdjuvants, AnesthesiaDrug ToleranceNociceptorsCyclohexanecarboxylic AcidsDouble-Blind MethodNaloxoneMethotrexateAnalgesics, Non-NarcoticBehavior, AnimalDrug Administration ScheduleCerebrospinal FluidCesarean SectionOligoclonal BandsTime FactorsPosterior Horn CellsAdrenergic alpha-AgonistsNarcotic AntagonistsCisterna MagnaLidocaineFormaldehydeInjections, IntravenousPhysical StimulationLeukemic InfiltrationAminesAnalgesia, EpiduralInfusion PumpsHyperesthesiaRadiation DosageSciatic NeuropathyLethal Dose 50Tetanus AntitoxinPeripheral Nervous System DiseasesPeripheral Nerve InjuriesDrug InteractionsAnesthesia, EpiduralMeningeal CarcinomatosisTreatment OutcomePrecursor Cell Lymphoblastic Leukemia-LymphomaAmitriptylineNociceptive PainCytarabineCarrageenanAdministration, OralNociceptionDisease Models, AnimalVisceral PainInjections, EpiduralInjections, IntraventricularMeperidineCerebrospinal Fluid RhinorrheaCentral Nervous System NeoplasmsReceptors, OpioidSpinal Nerve RootsReflexLigationLyme NeuroborreliosisDrug SynergismHot TemperatureSubstance Pomega-ConotoxinsCentral Nervous System DiseasesReceptors, Opioid, muKetorolacDrug Therapy, CombinationDexmedetomidine