[Selectivity of [D-Ala2-O-benzyl-Ser5]-enkephalin on mu and delta opiate receptor subtypes].
The selectively of [D-Ala2-O-benzyl-Ser5]- enkephalin(DABS) on mu and delta opiate receptor subtypes was studied by competing the binding of [3H] DADLE to the P2 fraction of the guinea pig brain homogenate and compared with mu agonist morphine and FW34-569 and delta agonist DADLE. DABS showed a high affinity to both mu and delta subtypes with about 10 times higher affinity to delta subtype. Therefore, DABS is less selective than DADLE on delta subtype.