1H homonuclear editing of rat brain using semiselective pulses.
We have used a semiselective Hahn spin-echo sequence of the form (1331)-tau-(2662)-tau-AQ, delivered by a surface coil to obtain high-resolution 1H NMR spectra from the brains of intact dead rats. This sequence gave suppression of the tissue water resonance by a factor of 80,000 when tau = 68 ms. Delivery of a frequency-selective Dante pulse train to the alpha-CH resonance of lactate at 4.11 ppm, simultaneously with the 2662 refocusing pulse, altered the j-modulation in the spin-coupled beta-CH3 protons. Subtraction of this spectrum from one in which the Dante was ineffective gave an edited spectrum containing only the beta-CH3 resonance of lactate at 1.31 ppm. When the position of the Dante was shifted to 3.78 ppm to selectively invert the alpha-CH protons of alanine, an edited spectrum of alanine was obtained.
Hetherington
H P
HP
Avison
M J
MJ
Shulman
R G
RG
D000409:Alanine / Q000032:analysis; D000818:Animals; D001923:Brain Chemistry; D007773:Lactates / Q000032:analysis; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D011522:Protons; D051381:Rats; D014867:Water
D007773:Lactates; D011522:Protons; D014867:Water; D000409:Alanine