Double-quantum surface-coil NMR studies of sodium and potassium in the rat brain.
Double-quantum filtered and conventional single-pulse sodium and potassium NMR spectra were obtained from in situ rat brain at 7.0 T. using a surface coil. In contrast to the ca. 14% decrease observed in single-pulse sodium NMR spectra upon death, increases as large as ca. 800% were observed in double-quantum filtered sodium spectra. Conversely, a ca. 26% increase was observed in single-pulse potassium spectra upon death, while double-quantum filtered potassium spectra decreased below the noise level, for the shortest preparation time used. The decay rate of double-quantum sodium coherence in the in situ rat brain after death was dependent upon the double-quantum preparation time: this behavior results from the nonuniformity of the brain, and may be related to physiological compartmentalization. The potential application to sodium NMR imaging of cerebral functionality is briefly discussed.
Lyon
R C
RC
Laboratory of Metabolism and Molecular Biology, National Institute on Alcohol Abuse and Alcoholism, Rockville, Maryland 20852.
Pekar
J
J
Moonen
C T
CT
McLaughlin
A C
AC
D000818:Animals; D001921:Brain / Q000033:anatomy & histology*; D001923:Brain Chemistry; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008297:Male; D011188:Potassium / Q000032:analysis*; D051381:Rats; D011916:Rats, Inbred F344; D012964:Sodium / Q000032:analysis*
D012964:Sodium; D011188:Potassium