RT Journal Article SR Electronic T1 Quantitative evaluation of cerebral blood flow and oxygen metabolism in the normal anesthetized rat: 15O-labeled gas inhalation PET with MRI fusion JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 1874 OP 1874 VO 53 IS supplement 1 A1 Watabe, Tadashi A1 Shimosegawa, Eku A1 Watabe, Hiroshi A1 Kanai, Yasukazu A1 Hanaoka, Kohei A1 Ueguchi, Takashi A1 Imaizumi, Masao A1 Kato, Hiroki A1 Tatsumi, Mitsuaki A1 Hatazawa, Jun YR 2012 UL http://jnm.snmjournals.org/content/53/supplement_1/1874.abstract AB 1874 Objectives The purpose of this study was quantitative measurement of cerebral blood flow (CBF), cerebral metabolic rate of oxygen (CMRO2), oxygen extraction fraction (OEF), and cerebral blood volume (CBV) by steady state inhalation method in the normal anesthetized rat. Methods Eight normal male Sprague-Dawley rats (body weight=268±14g) under anesthesia were investigated in this study. Tracheotomy was performed and airway tube was placed into the trachea, which connected to the ventilator (tidal volume: 3ml, frequency: 60/min). The CBF and OEF were measured under artificial ventilation of 15O-CO2 and 15O-O2 gases delivered through the radioactive gas stabilizer (16min for each study), respectively. CBV was measured by 15O-CO gas inhalation for 12min and used for the correction of intravascular hemoglobin-bound 15O2. Arterial blood sampling (0.1ml) was performed during each 15O-labeled gas study to measure the radioactivity of whole blood and plasma. MRI was performed with the same holder after PET acquisition. Regions of interests were placed on the whole brain of PET images with reference to the semi-automatically co-registered PET/MRI fused images. Results The total time of the whole PET scan of each rat was 73.3±5.8 (68 to 85) min. In both 15O-CO2 and 15O-O2 study, radioactivity count of the brain reached steady state approximately 10 min after the continuous 15O gas inhalation. Quantitative PET data in the whole brain were as follows: CBF, 32.3 ± 4.5 mL/100ml/min; CMRO2, 3.23 ± 0.42 mL/100ml/min; OEF, 64.6 ± 9.1 %; and CBV, 5.05 ± 0.45 mL/100ml. Conclusions This study demonstrated quantitative PET measurement of CBF, CMRO2, and OEF by steady-state method of 15O-CO2 and 15O-O2 gases; CBV by 15O-CO gas in the normal anesthetized rat