1971 年 10 巻 p. 4-8
The effect of catecholamine on formation of cyclic 3', 5' -AMP in incubated slices of brain was examined either by using the slices pre-labeled with 14C-adenine and by measuring the conversion rate of the incorporated 14C to 14C-cyclic AMP or by assaying the cyclic AMP content in the incubated slices after enzymic conversion to ATP. A comparative study with 6 different mammals indicated that adenyl cyclase of human cerebral cortex is most sensitive to norepinephrine, having a characteristic of the β -adrenergic receptor. Norepinephrine, histamine and serotonin showed synergistic effects each other as to stimulation of cerebral adenyl cyclase of a guinea pig. Mem-brane depolarization elicited by high potassium ions or depolarizing agents, such as veratridine and ouabain, potentiated the effect of norepinephrine in both guinea pig and human cerebral cortex.
Synergism between membrane depolarization and catecholamine suggests that catecholamine would be a secondary modifier of brain adenyl cyclase while the electrical activity would be a primary one. Significance of occurrence of norepinephrinesensitive adenyl cyclase in human brain was discussed in relevance to pathogenesis of affective psychosis.