Adenylate cyclase in rat synaptosomal plasma membranes and caudate nucleus homogenate: effects of dopamine, E prostaglandins, guanyl-5'-yl-imidodiphosphate and morphine.

The adenylate cyclase in two particulate preparations from rat brain, a homogenate from caudate nucleus (CN-homogenate) and a synaptosomal plasma membrane fraction (SPM-fraction) from whole rat brain was investigated. Stimulation of the enzyme by dopamine and prostaglandins E1 and E2 was found in the CN-homogenate while only a weak prostaglandin E1 and E2 stimulation and no dopamine stimulation could be found in the SPM-fraction. Guanyl-5'-yl-imidophosphate (GppNHp) and NaF could stimulate the adenylate cyclase in both preparations. Morphine up to 10(-5) M altered neither the basal enzyme activity nor any of the stimulated enzyme activities.