Feasibility of mapping unidirectional Pi-to-ATP fluxes in muscles of the lower leg at 7.0 Tesla

作者：Parasoglou Prodromos^*; Xia Ding; Regatte Ravinder R

来源：Magnetic Resonance in Medicine, 2015, 74(1): 225-230.

DOI：10.1002/mrm.25388

• saturation transfer
• P-31-MRI
• musculoskeletal MRI
• nonproton MRI

PurposeTo assess the feasibility of mapping the kinetics and unidirectional fluxes of inorganic phosphate (Pi) to adenosine triphosphate (ATP) reactions in the entire volume of the lower leg muscles using a three-dimensional saturation transfer (ST) phosphorus (P-31) imaging sequence.
Theory and MethodsWe imaged the lower leg muscles of five healthy subjects at 7.0 Tesla. The total experimental time was 45 min. We quantified muscle-specific forward reaction rate constants (k(f)) and metabolic fluxes (V-f) of the Pi-to-ATP reaction in the tibialis anterior, the gastrocnemius, and the soleus.
ResultsIn the tibialis anterior, k(f) and V-f were 0.11 s(-1)0.03 (mean +/- standard deviation) and 0.34 mM s(-1)+/- 0.10, respectively. In the gastrocnemius, k(f) was 0.11 s(-1)+/- 0.04 and V-f was 0.37 mM s(-1)+/- 0.11, while in the soleus muscle k(f) was 0.10 s(-1)+/- 0.02 and V-f was 0.36 mM s(-1)+/- 0.14.
ConclusionOur results suggest that mapping the kinetics and unidirectional fluxes from Pi-to-ATP in both the anterior and posterior muscles of the lower leg is feasible at ultra-high field and may provide useful insights for the study of insulin resistance, diabetes and aging. Magn Reson Med 74:225-230, 2015.

• 出版日期2015-7