Quantitative proton spectroscopy of canine brain: in Vivo and in Vitro correlations

Peter B. Barker, Steven N. Breiter, Brian J. Soher, John C. Chatham, John R. Forder, Michael A. Samphilipo, Carolyn A. Magee, James H. Anderson

Research output: Contribution to journalArticlepeer-review

Abstract

Quantitative, single‐voxel proton NMR spectroscopy of normal brain was performed in five adult beagle dogs using the cerebral water signal as an internal intensity reference. The same brain regions were then rapidly isolated and frozen using a pneumatic biopsy drill, perchloric acid extracted, and analyzed by biochemical assay and high‐resolution NMR spectroscopy. The concentrations of the major resonances in the in vivo and in vitro spectra were compared, and good agreement was found between the different measurements. The in vivo spectra contained three peaks at 3.21, 3.04, and 2.02 ppm, which are usually assigned to trimethylamines (TMA), creatines, and N‐acetyl derivatives (NAc), which corresponded to be the following metabolite concentration values: 1.7 ± 0.6, 7.7 ± 2.1, and 10.9 ± 2.7 μmol/g wet weight respectively. In vitro, the following metabolite concentrations were measured: glycerophosphocholine (GPC) 1.3 ± 0.2, phosphocholine (PC) 0.5 ± 0.1, phosphocreatine (PCr) 2.6 ± 0.4, creatine (Cr) 5.9 ± 1.4, and N‐Acetyl aspartate (NAA) 8.9 ± 1.8 μmol/g wet weight. Therefore, the 3.21 ppm resonance observed in the in vivo spectrum is predominantly GPC and PC in a ratio of 2.6:1, the 3.04 ppm resonance is Cr and PCr in a ratio of 2.3:1, and the 2.02 ppm resonance is predominantly (≈80%) NAA with small contributions from N‐acetylaspartyl‐glutamate (NAAG) and glutamate. The data presented here validate the technique of water referencing as a simple and convenient means of quantitating single‐voxel in vivo proton NMR spectra of the brain.

Original languageEnglish (US)
Pages (from-to)157-163
Number of pages7
JournalMagnetic resonance in medicine
Volume32
Issue number2
DOIs
StatePublished - Aug 1994

Keywords

  • canine brain
  • proton NMR spectroscopy
  • quantitation

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging

Fingerprint Dive into the research topics of 'Quantitative proton spectroscopy of canine brain: in Vivo and in Vitro correlations'. Together they form a unique fingerprint.

Cite this