LONG EXPERIMENTAL DURATIONS ARE REQUIRED FOR DOUBLE LABEL [C-14] DEOXYGLUCOSE AND [H-3] 2-DEOXYGLUCOSE AUTORADIOGRAPHIC METHODS

Double-label 2-deoxyglucose (2-DG) studies using sequential [C-14]- and [H-3]2-DG injections demonstrate increased [C-14]2-DG uptake during the first and second stimulation periods. To understand why this occurs, the rat mystacial vibrissae were stimulated at various times following [C-14]2-DG injection. Local cerebral glucose utilization (LCGU) increased when whisker stimulation was performed at 0-90 min following [C-14]2-DG injection. LCGU did not increase when whisker stimulation was performed at 90-150 min following [C-14]2-DG injection. To minimize contamination of the two tracers in double label 2-DG mapping studies, the time between [C-14]- and [H-3]2-DG administration should be increased to 90 min.