Enkephalin morphine antagonism

Morphine Antagonism. In order to verify that morphine competes with enkephalin for binding to PS we added morphine sulfate pentahydrate CIO mg) to a mixture of [2-[2- C]glycine]enkephalin Cl.2 mg) and PS C20 mg) in D2O at "pH" 6.3. Under this condition, the Itnewidth and intensity of the glycyl-2 resonance reverted to those of free enkephalin. Under similar conditions, but with PS C3Q mg) and morphine sulfate pentahydrate (5.4 mg), the linewidth and intensity of the glycyl-2 resonance was again essentially that of free enkephalin. 

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