A method for measuring cerebral glucose metabolism in vivo by 13 C‐NMR spectroscopy

Current methods for estimating the rate of cerebral glucose utilization (CMR glc ) typically measure metabolic activity for 40 min or longer subsequent to administration of [ 13 C]glucose, 2‐[ 14 C]deoxyglucose, or 2‐[ 18 F]deoxyglucose. We report preliminary findings on estimating CMR glc for a period of 15 min by use of 2‐[6‐ 13 C]deoxyglucose. After a 24‐hr fast, rats were anesthetized, infused with [1‐ 13 C]glucose for 50 min, and injected with 2‐[6‐ 13 C]deoxyglucose (500 mg/kg). During the subsequent 12.95 min the estimated value of CMR glc was 0.6 ± 0.4 micromol/min/g (mean ± SD, N = 7), in agreement with values reported for anesthetized rats studied with the 2‐[ 14 C]deoxyglucose method and other 13 C‐NMR methods that measure CMR glc . In rats injected with bicuculline methiodide (a known stimulant of CMR glc ), CMR glc increased by more than 75% during 12.95 min following injection of bicuculline (Wilcoxon signed rank test, P = 0.042, N = 8). Magn Reson Med 48:1063–1067, 2002. © 2002 Wiley‐Liss, Inc.