The dopamine-sensitive adenylate cyclase of the rat caudate nucleus—3. The effect of aporphines and protoberberines

A series of aporphines and protoberherines were tested for activity with da and beta-type adenylate cyclases. Loss of da agonist but not antagonist activity of apomorphine was associated with the removal or methylation of the hydroxyls or the S-configuration. The effects of other alterations in structure were not as clear-cut and alterations in antagonist activity were not similar in the two enzyme systems. Surprisingly the protoherberines were fairly potent as inhibitors of the da-cyclase with little effects on the beta system. In most situations the S-isomer was much more potent than the R-antipode. None of the compounds studied possessed beta-agonist activity.