JOURNAL HOME CME HOME THIS MONTH PAST ISSUES ETOC COLLECTIONS AUTHORS REVIEWERS EDITORIAL BOARD FEEDBACK RSS HELP
		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Hunter, L. W. Articles by Tyce, G. M. Search for Related Content PubMed PubMed Citation Articles by Hunter, L. W. Articles by Tyce, G. M.

Norepinephrine Uptake in Canine Saphenous Veins in the Presence and Absence of Halothane

Received from the Departments of Anesthesiology and of Physiology and Biophysics, Mayo Clinic and Mayo Foundation, Rochester, Minnesota.

Abstract

Studies were done to examine neuronal and extraneuronal uptakes of norepinephrine in canine saphenous veins and to ascertain whether these uptakes were altered by halothane. Minced vein was incubated for 1 vain in Krebs-Ringer solution containing L-[ring-2,5,6-³H]-norepinephrine (1, 2.5, 6, or 12 µM). After incubation, radioactivity in tissue was measured by liquid scintillation counting. Neuronal uptake at each norepinephrine concentration was determined by the difference in norepinephrine uptake between tissues in which both neuronal and extraneuronal uptakes were operative and in tissues in which only extraneuronal uptake was operative. In time studies with 1 µM norepinephrine, neuronal uptake was still dominant at 10 min; with 12 µM norepinephrine, extraneuronal uptake predominated at all incubation periods tested. In other studies, tissues were incubated in the absence or presence of halothane (2.5%). The K_m values for neuronal uptake in control and halothane-treated tissues were 2.49 and 2.32 µM, respectively. Corresponding V_max values were 0.049 and 0.060 nMol·min^–1.100 mg^–1, respectively. No significant effect of halothane on neuronal or extraneuronal uptake could be detected.

Key Words: ANESTHETICS, VOLATILE—halothane • SYMPATHETIC NERVOUS SYSTEM—neuronal norepinephrine uptake

Anesthesia & Analgesia® is published for the International Anesthesia Research Society® by Lippincott Williams & Wilkins with the assistance of Stanford University Libraries' HighWire Press®. Copyright 2006 by the International Anesthesia Research Society. Online ISSN: 1526-7598   Print ISSN: 0003-2999