Sympathomimetic amine-induced release of norepinephrine-3H from different intraneuronal storage compartments

The effects of different loading procedures on norepinephrine-3H (NE-3H) efflux induced by a structurally analogous group of indirectly acting sympathomimetic amines was examined in rabbit vas deferens. (+)-Amphetamine was ineffective in releasing 3H from tissues with intact intraneuronal storage granules but was an effective depletor of (a) non-granular intraneuronal compartment(s) following in vivo treatment with reserpine. (+/-)-p-Hydroxynorephedrine was a less effective depletor of non-granular NE-3H. These experiments provide further evidence in support of multiple intraneuronal storage compartments which can be pharmacologically differentiated by utilizing indirectly acting sympathomimetic amine agents.