Regional variations and the effects of age and gender on glutamate concentrations in the human brain

Department of Medicine, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI 96813, USA.
Magnetic Resonance Imaging (Impact Factor: 2.09). 06/2008; 26(5):667-75. DOI: 10.1016/j.mri.2007.06.007
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Proton magnetic resonance spectroscopy was performed at 3 T using the echo time-averaged point-resolved spectroscopy method to determine the effects of age, gender and brain region on glutamate (Glu) concentrations in the healthy human brain. Thirty healthy men and 20 healthy women aged between 21 and 71 years were studied. Significant regional variations of Glu concentrations were observed. Glu concentration in the gray matter (GM) was approximately 25% higher than that in the white matter. Significant age-dependent decreases in Glu concentrations were observed in the basal ganglia (r=-0.75, P<.001) and parietal GM (r=-0.66, P<.001) of men but not those of women. Our findings demonstrate regional variations of Glu concentrations and suggest that the male brain may be more vulnerable to aging than the female brain. Our results also highlight the importance of brain region, age and gender matching in clinical studies.

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    • "Our Glu findings are in contrast with the literature in the general population, which suggests an age-related decline in Glu or no age-related change (Marsman et al. 2013; Sailasuta et al. 2008). An MRS study in the general population showed that Gln tended to increase with age (Kaiser et al. 2005), whereas our findings in plasma were in the opposite direction. "
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