NMR "diffusion-diffraction" of water revealing alignment of erythrocytes in a magnetic field and their dimensions and membrane transport characteristics.
"Diffusion-diffraction" experiments on water, yielding "q-space" plots, were conducted on suspensions of oxygenated (diamagnetic) human erythrocytes. (i) These suspensions displayed diffusion-diffraction of water; (ii) the shape of the q-space plots depended on the direction along which the diffusion was measured, thus implying alignment of the cells in the magnetic field of the NMR spectrometer; (iii) the diffusion anisotropy was altered in a predictable way by converting the hemoglobin to a paramagnetic form; (iv) the shapes of the q-space plots were altered in a predictable way by inhibiting water transport; (v) the pseudo-first order rate constant characterizing the covalent inhibition of water transport, by p-chloromercuribenzenesulfonate (p-CMBS), was measured; and (vi) the cell diameter and intercellular spacing were measured from the positions of the interference minima and maxima in the q-space plots. The relevance of these findings to NMR-based histological characterization of tissues, and the implications, for magnetic resonance imaging (MRI), of erythrocyte alignment in the small vessels of the brain in particular, are noted.
Kuchel
P W
PW
Department of Biochemistry, University of Sydney, Australia.
Coy
A
A
Stilbs
P
P
D016880:Anisotropy; D004058:Diffusion; D004910:Erythrocyte Membrane / Q000378:metabolism; D004912:Erythrocytes / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D006400:Hematocrit; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008280:Magnetics; D013696:Temperature; D014867:Water / Q000378:metabolism
D014867:Water