Efficient 31P band inversion transfer approach for measuring creatine kinase activity, ATP synthesis, and molecular dynamics in the human brain at 7 T

Research output: Contribution to journalArticle

6 Scopus citations

Abstract

Purpose: To develop an efficient 31P magnetic resonance spectroscopy (MRS) method for measuring creatine kinase (CK) activity, adenosine triphosphate (ATP) synthesis, and motion dynamics in the human brain at 7 Tesla (T). Methods: Three band inversion modules differing in center frequency were used to induce magnetization transfer (MT) effect in three exchange pathways: (i) CK-mediated reaction PCr → γ-ATP; (ii) de novo ATP synthesis Pi → γ-ATP; and (iii) ATP intramolecular 31P–31P cross-relaxation γ-(α-) ↔ β-ATP. The resultant MT data were analyzed using a 5-pool model in the format of magnetization matrix according to Bloch-McConnell-Solomon formalism. Results: With a repetition time (TR) of 4 s, the scan time for each module was approximately 8 min. The rate constants were kPCr → γATP 0.38 ± 0.02 s−1, kPi → γATP 0.19 ± 0.02 s−1, and σγ(α) ↔ βATP 0.19 ± 0.04 s−1, corresponding to ATP rotation correlation time τc (0.8 ± 0.2) ·10−7 s. The T1 relaxation times were Pi 7.26 ± 1.76 s, PCr 5.99 ± 0.58 s, γ-ATP 0.98 ± 0.07 s, α-ATP 0.95 ± 0.04 s, and β-ATP 0.68 ± 0.03 s. Conclusion: Short-TR band inversion modules provide a time-efficient way of measuring brain ATP metabolism and could be useful in studying metabolic disorders in brain diseases. Magn Reson Med 78:1657–1666, 2017.

Original languageEnglish (US)
Pages (from-to)1657-1666
Number of pages10
JournalMagnetic resonance in medicine
Volume78
Issue number5
DOIs
StatePublished - Nov 2017

Keywords

  • 31P MRS
  • ATP
  • human brain
  • inversion transfer
  • magnetization transfer
  • relaxation time

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging

Fingerprint Dive into the research topics of 'Efficient <sup>31</sup>P band inversion transfer approach for measuring creatine kinase activity, ATP synthesis, and molecular dynamics in the human brain at 7 T'. Together they form a unique fingerprint.

  • Cite this