Evaluation of a Double-Tracer Autoradiographic Technique for the Measurement of Both Local Cerebral Glucose Metabolism and Local Cerebral Blood Flow

A solvent washout technique is evaluated that could be used to remove one 14 C tracer after a combined autoradiographic CMRglu and CBF study using [ 14 C]2-deoxyglucose (2DG) and [ 14 C]iodoantipyrine (IAP). The technique permits the simultaneous measurement of local CBF and local CMRglu in the same animal without the use of the short-lived tracers of iodine, 123 I and 131 I, for iodoantipyrine labeling. This report shows that brain tissue sections did not retain 14 C from [ 14 C]2DG when chloroform was used as the washout solvent. Chloroform washing removes nearly all the 14 C from [ 14 C]IAP. For this study, careful attention was given to the control, pre-wash measurement of 14 C concentration.