PT - JOURNAL ARTICLE AU - Steven Locke AU - Gerald Cohen AU - Dorothy Dembiec TI - UPTAKE AND ACCUMULATION OF <sup>3</sup>H-6,7-DIHYDROXY-TETRAHYDROISOQUINOLINE BY PERIPHERAL SYMPATHETIC NERVES <em>IN VIVO</em> DP - 1973 Oct 01 TA - Journal of Pharmacology and Experimental Therapeutics PG - 56--67 VI - 187 IP - 1 4099 - http://jpet.aspetjournals.org/content/187/1/56.short 4100 - http://jpet.aspetjournals.org/content/187/1/56.full SO - J Pharmacol Exp Ther1973 Oct 01; 187 AB - 3H-6,7-dihydroxytetrahydroisoquinoline was prepared by condensation of 3H-dopamine with formaldehyde. When administered intravenously, this 3H-alkaloid was taken up into the mouse heart and into the submaxillary glands and irides of rats. Additionally, uptake into adrenal glands was also observed. Confirmation that uptake was into sympathetic nerve terminals of the heart was achieved by experiments with chemically denervated (6-hydroxydopamine-treated) mice, and by use of catecholamine uptake inhibitors (cocaine and desmethylimipramine). These treatments diminished uptake of the 3H-alkaloid into the heart by 48 to 79%. Similarly, uptake specifically into nerve terminals of the iris and submaxillary gland was identified in experiments with surgically denervated rats (unilateral superior cervical ganglionectomy). Denervation reduced the 3H-alkaloid by 75 to 84% in the iris and by 39 to 53% in the submaxillary gland. The 3H-alkaloid in aluminum hydroxide-purified extracts of tissues was identified by thinlayer chromatography. In denervated preparations, or after cocaine or desmethylimipramine, the 3H-alkaloid was more extensively metabolized. Neuronal 3H-alkaloid was relatively protected from metabolic transformation. The relationship of these observations to a hypothesis about tetrahydroisoquinoline biosynthesis from endogenous catecholamines during ethanol metabolism is discussed. © 1973 by The Williams &amp; Wilkins Company