PenicillamineEnkephalinsEnkephalin, MethionineEnkephalin, LeucineGold Sodium ThiomalateEnkephalin, Ala(2)-MePhe(4)-Gly(5)-Enkephalin, Leucine-2-AlanineEnkephalin, D-Penicillamine (2,5)-Hepatolenticular DegenerationS-Nitroso-N-AcetylpenicillamineEndorphinsSulfasalazineAurothioglucoseArthritis, RheumatoidAuranofinTartratesCystinuriaReceptors, OpioidDimercaprolReceptors, Opioid, deltaDrug EruptionsReceptors, Opioid, muChelating AgentsOrganogold CompoundsBlood SedimentationAntimonyNaloxoneNitric Oxide DonorsSulfhydryl CompoundsAminopropionitrileMyasthenia GravisCopperSchistosomicidesGoldReceptors, SomatostatinDose-Response Relationship, DrugDynorphinsAzathioprineEthylketocyclazocineCyclazocineNitric OxideNarcotic AntagonistsMorphineProteinuriaRadioligand AssayBenzomorphansTime FactorsNaltrexone