Nmr microscopy of single neurons under hypotonic perturbation.
Hsu, Edward W., Nanci R. Aiken, Stephen J. Blackband.
Department of Biomedical Engineering and 5Department of Radiology,
The Johns Hopkins University School of Medicine, 720 Rutland Avenue,
Baltimore, MD 21205, Department of Radiology, Duke University Medical
Center, DUMC Box 3302, Durham, NC 27710
APStracts 3:0226C, 1996.
Nuclear magnetic resonance (NMR) characteristics of water in perfused
single neurons undergoing a 20% hypotonic perturbation were examined
quantitatively using NMR microscopy. The T2 relaxation times in the
cytoplasm and nucleus increased by 24.0 8.5% (average standard error,
n=8) and 29.7 5.3% (n=6), respectively, while the apparent diffusion
coefficients (ADCs) showed no significant change. These findings are
consistent with the behaviors of a perfect osmometer and with
accepted molecular relaxation and diffusion models, and have
significant impacts on current views of properties of cellular water.
Further, the results suggest that the increase of tissue
intra/extracellular volume ratio during cell swelling is the
predominant mechanism underlying the ADC reduction in acute brain
ischemia. These data are the first direct quantitative measurements
of the NMR characteristics of water in the cytoplasm and nucleus of
single cells undergoing physiological perturbations and may lead to
an improved diagnostic capability for NMR imaging in a variety of
disease states.
Received 2 April 1996; accepted in final form 26 June 1996.
APS Manuscript Number C181-6.
Article publication pending Am. J. Physiol. (Cell Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 25 July 1996