Determination of intracellular calcium in vivo via fluorine-19
nuclear magnetic resonance spectroscopy.
Song, Sheng-Kwei, Richard S. Hotchkiss, Jeffrey Neil, Philip E.
Morris, Jr, Chung Y. Hsu, and Joseph J. H. Ackerman.
Department of Chemistry, Washington University, One Brookings
Drive, St. Louis, MO 63130-4899, Department of Chemistry, University
of Alabama at Birmingham, Birmingham, AL 35294, and Departments of
Anesthesiology, Medicine and Neurology, Washington University School
of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110-1093
APStracts 2:0120C, 1995.
Fluorine-19 NMR spectroscopic detection of the NMR active calcium
indicator 5,5_-difluorobis(2-amionphenoxy)ethane-N,N,N_,N_
-tetraacetate (5FBAPTA) is one method for measuring cytosolic free
calcium concentration ([Ca2+]i), and has been used previously to
measure [Ca2+]i in isolated cells and perfused organs. The aim of the
present investigation was to demonstrate the feasibility of
determining [Ca2+]i in vivo and in situ using 19F NMR and 5FBAPTA.
Experiments were performed on male Sprague-Dawley rats with a surface
coil antenna employed for NMR interrogation. The Ca2+ indicator
5FBAPTA was infused either intravenously (kidney, spleen) or
intraventricularly (brain) as a 100 mg/ml solution of the cell
permeant acetoxymethylester (5FBAPTA-AM) in dimethylsulfoxide (DMSO).
Rats tolerated intravenous infusion without evident change in mean
arterial blood pressure. In all tissues examined _ kidney, spleen and
brain _ [Ca2+]i was ca. 200 nM. To our know ledge, these results
represent the first in vivo and in situ determinations of [Ca2+]i
employing 19F NMR.
Received 18 August 1994; accepted in final form 13 January 1995.
APS Manuscript Number C491-4.
Article publication pending Am. J. Physiol. (Cell Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 10 March 1995.