Ethanol alters kinetic characteristics and function of striatal morphine receptors

Morphine was shown to promote dopamine (DA) synthesis and release in mouse striatum, but mice rendered tolerant and dependent on ethanol were found to be less responsive to morphine's effects on striatal DA metabolism than control animals. Ethanol feeding also produced a change in the affinity of striatal "opiate" receptors for [3H]dihydromorphine, and these ethanol-induced receptor changes may be responsible for the altered biological effect of morphine.