NOE ENHANCEMENTS AND T-1 RELAXATION-TIMES OF PHOSPHORYLATED METABOLITES IN HUMAN CALF MUSCLE AT 1.5-TESLA

Nuclear Overhauser effect (NOE) enhancements and relaxation times of P-31 metabolites in human calf were measured in 12 volunteers (4 men and 8 women) at 1.5 T using a dual tuned four-ring birdcage. The NOE enhancements of inorganic phosphate (P-i), phosphocreatine (PCr), gamma-, alpha-, and beta-nucleoside triphosphate (NTP) from 19 measurements were 0.51 +/- 0.10, 0.64 +/- 0.03, 0.53 +/- 0.03, 0.56 +/- 0.08, and 0.47 +/- 0.05, respectively. The relaxation times were independent of proton irradiation and from 23 measurements were 3.49 +/- 0.35, 4.97 +/- 0.58, 4.07 +/- 0.36, 2.90 +/- 0.25, and 3.61 +/- 0.25 s for P-i, PCr, gamma-, alpha-, and beta-NTP, respectively. No significant differences between gender and age were observed for either NOE enhancements or relaxation times. Also, among nine volunteers, we observed no significant differences in T-1 between the coupled and decoupled cases.