Calmodulin-dependent adenylate cyclase in rat retina and the response to dopamine.

Adenylate cyclase activity from the rat neural retina was highly stimulated with Ca2+ and calmodulin. The retinal adenylate cyclase activity was also increased by dopamine, and the activation was not changed with or without Ca2+-calmodulin in fractions from the neural retina homogenate after sucrose density gradient centrifugation. The results suggest that the two regulation systems (i.e. dopamine and Ca2+-calmodulin) of adenylate cyclase in the rat retina appear to be independent.