Sympathomimetic Amine-Induced Release of Norepinephrine-³H from Different Intraneuronal Storage Compartments

Abstract

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-Hy-droxynorephedrine 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.

Release of endogenous ATP from the vasa deferentia of the rat and guinea‐pig by the indirect sympathomimetic tyramine

“…Alternative reasons for the apparent insensitivity of the guinea-pig vas deferens have been put forward, for example, the existence of tyramine-insensitive pools of NA (Takimoto, Amiri & Cho, 1981). The present findings do not support such a theory, since in this study tyramine significantly enhanced the release of [3H]-NA.…”

A Chemical Perspective of Pharmacology and Toxicology

“…Graduate students Glenn Takimoto and Joseph Fischer studied the Amp-based efflux of norepinephrine from preloaded sympathetically innervated tissues (37,38) and brain synaptosomes (39,40). Based on the results of these studies, we proposed an exchange diffusion-based model for Amp-induced catecholamine efflux from nerve terminals (34).…”

Untitled

“…To address the relevance of the Amp and phentermine metabolic pathways to their neurochemistry, the biological component of our laboratory began studies on the catecholaminergic nerve terminal as the target of the Amp class of compounds. Graduate students Glenn Takimoto and Joseph Fischer studied the Amp-based efflux of norepinephrine from preloaded sympathetically innervated tissues (37,38) and brain synaptosomes (39,40). Based on the results of these studies, we proposed an exchange diffusion-based model for Amp-induced catecholamine efflux from nerve terminals (34).…”