Stimulation of cyclic adenosine 3',5'-monophosphate formation in rabbit choroid plexus by beta-receptor agonists and vasoactive intestinal polypeptide

The formation of cyclic adenosine 3',5'-monophosphate (cAMP) was determined in blood-free choroid plexus homogenates from all ventricles of rabbit using a competitive protein binding technique. Previous stimulation of the intact plexus tissue in vitro with sympathomimetic drugs or vasoactive intestinal polypeptide (VIP) leads to increased local synthesis of cAMP. Tests with selective beta-receptor agonists and antagonists suggested that beta 1-receptors predominate, which is consistent with studies of sympathomimetic effects on cerebrospinal fluid production in vivo.