TY - JOUR

T1 - The effect of sample freezing on proton magic-angle spinning NMR spectra of biological tissue

AU - Middleton, David A.

AU - Bradley, Daniel P.

AU - Connor, Susan C.

AU - Mullins, P G

AU - Reid, David G.

PY - 1998/7/1

Y1 - 1998/7/1

N2 - Magic-angle spinning (MAS) has recently been shown to enhance spectral resolution in NMR examinations of intact biological tissue ex vivo. This work demonstrates that freezing certain tissue samples before examination by 1H MAS NMR can have a marked effect on their spectra. Spectra of rat kidney after freezing in liquid nitrogen, compared with spectra before freezing, showed a significant increase in signal intensities from alanine (>100%), glutamine (>40%), and glycine (>100%), and a decrease in signals assigned to lipids and other macromolecules. Some resonances--such as from leucine, valine, isoleucine, and aspartate--only became visible after freezing the tissue. These observations suggest that low temperature storage of tissue necropsies or biopsies might affect the results of a MAS NMR analysis, possibly resulting in the misinterpretation of metabolite changes to pathogen or disease effects.

AB - Magic-angle spinning (MAS) has recently been shown to enhance spectral resolution in NMR examinations of intact biological tissue ex vivo. This work demonstrates that freezing certain tissue samples before examination by 1H MAS NMR can have a marked effect on their spectra. Spectra of rat kidney after freezing in liquid nitrogen, compared with spectra before freezing, showed a significant increase in signal intensities from alanine (>100%), glutamine (>40%), and glycine (>100%), and a decrease in signals assigned to lipids and other macromolecules. Some resonances--such as from leucine, valine, isoleucine, and aspartate--only became visible after freezing the tissue. These observations suggest that low temperature storage of tissue necropsies or biopsies might affect the results of a MAS NMR analysis, possibly resulting in the misinterpretation of metabolite changes to pathogen or disease effects.

KW - Animals

KW - Culture Techniques

KW - Disease Models, Animal

KW - Freezing

KW - Kidney

KW - Magnetic Resonance Spectroscopy

KW - Protons

KW - Rats

KW - Rats, Sprague-Dawley

KW - Reference Values

KW - Reproducibility of Results

KW - Comparative Study

KW - Journal Article

U2 - 10.1002/mrm.1910400122

DO - 10.1002/mrm.1910400122

M3 - Article

C2 - 9660567

VL - 40

SP - 166

EP - 169

JO - Magnetic Resonance in Medicine

JF - Magnetic Resonance in Medicine

SN - 0740-3194

IS - 1

ER -