Premium
Interdependence of N ‐acetyl aspartate and high‐energy phosphates in healthy human brain
Author(s) -
Pan Jullie W.,
Takahashi Kan
Publication year - 2005
Publication title -
annals of neurology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 4.764
H-Index - 296
eISSN - 1531-8249
pISSN - 0364-5134
DOI - 10.1002/ana.20317
Subject(s) - phosphocreatine , creatine , hippocampal formation , hippocampus , chemistry , endocrinology , medicine , occipital lobe , energy metabolism , creatine kinase , biology , neuroscience
Because cellular and extract data have suggested that N ‐acetylaspartate (NAA) reflects neuronal mitochondrial function, we evaluated the quantitative relationship between NAA, high‐energy phosphates, and ADP levels in the hippocampus and occipital lobe of 15 healthy volunteers. The ADP levels are calculated using the creatine kinase equilibrium and quantified 31 P and total creatine measurements. Using high‐field quantitative MR spectroscopic imaging, we find that NAA and ADP concentrations in the hippocampal body are 9.7 ± 1.5mM and 35 ± 8μM, respectively. In the occipital lobe, NAA and ADP are 11.9 ± 1.9mM and 32 ± 12μM, respectively. There is a statistically significant positive correlation between NAA and ADP, with R = +0.80, p < 2 × 10 −7 in the hippocampal body. In an adjacent hippocampal NAA voxel, the correlation between NAA and ADP had a R = +0.62, p < 3 × 10 −4 , whereas, in the occipital lobe, R = +0.67, p < 5 × 10 −5 . There was no significant relationship NAA and either ATP or phosphocreatine. This positive relationship of NAA with ADP suggests a directional process wherein energetics may modulate mitochondrial function. Ann Neurol 2004.