Alpha-adrenergic modulation of cyclic AMP formation in rat CNS: highest level in olfactory bulb.

The cyclic adenosine monophosphate response to catecholamines in the rat brain is mediated by beta-adrenergic receptors which activate adenylate cyclase and by alpha-adrenergic receptors which potentiate the response to beta-stimulation. We have found that the alpha-potentiation effect in the olfactory bulb is 2-3X greater than in other forebrain areas. This correlates with the extremely high density of alpha-receptors in this brain region and makes it a useful model for the study of alpha-receptor function.