NONINVASIVE MEASUREMENT OF CEREBRAL BLOOD-FLOW AND GLUCOSE METABOLIC-RATE IN THE RAT WITH HIGH-RESOLUTION ANIMAL POSITRON EMISSION TOMOGRAPHY (PET) - A NOVEL IN-VIVO APPROACH FOR ASSESSING DRUG-ACTION IN THE BRAINS OF SMALL ANIMALS

The cerebral metabolic rate of glucose (CMRglc) and cerebral blood flo w (CBF) in rats were estimated noninvasively with a high-resolution an imal positron emission tomography (PET) system that we recently develo ped. Quantifications of CMRglc and CBF were attempted with radiotracer s, F-18-2-fluoro-2-deoxyglucose and O-15-water, respectively. From the data obtained with PET, the CMRglc and CBF values under pretreatment conditions were respectively calculated as 51+/-14 mu mol/min/100g and 61+/-7 ml/min/100g under pentobarbital-anesthesia. These values were in close agreement,vith published data obtained,vith the autoradiograp hic technique. Moreover, an increase of 69% (mean) in CBF was detected after i.v. acetazolamide administration. The results indicate that th is high-resolution animal PET scanner holds great potential for the as sessment of drug-related metabolic and circulatory effects in intact a nd experimental animals.