Specificity of action of 6-hydroxydopamine in peripheral cat tissues:: Epletion of noradrenaline without depletion of 5-hydroxytryptamine

Abstract Recent work has established that 6-hydroxydopamine (6-OHDM) depletes tissues of noradrenaline (NA) 1, 2, 3, 4, 5 and also lessens responses to sympathetic nerve stimulation 6 by a mechanism that involves either uptake and storage 2, 7 or uptake and metabolism of 6-OHDM 3 . As it has been shown that the effect of 6-OHDM in the brain is specific to noradrenergic neurons without affecting nerves containing 5-hydroxytryptamine (5-HT) 8 , we thought it would be of interest to use 6-OHDM as a tool to investigate whether 5-HT is stored in peripheral sympathetic nerves of the cat. If a significant amount of 5-HT were stored in sympathetic nerves, the 5-HT tissue content should decrease when the sympathetic nerves are destroyed.