title: [1-11C]Octanoate as a PET tracer for studying ischemic stroke: evaluation in a canine model of thromboembolic stroke with positron emission tomography.
abstract: Octanoate is taken up by the brain and converted in astrocytes to glutamine through the TCA cycle after beta-oxidation. Consequently, [1-11C]octanoate might serve as a useful positron emission tomography (PET) probe for studying cerebral oxidative metabolism and/or astroglial functions. The present study attempted to evaluate the utility of using [1-11C]octanoate as a PET tracer for imaging and evaluating the pathophysiology of ischemic stroke. We used a canine model of thromboembolic stroke. Five male beagle dogs were implanted with an indwelling catheter in the left internal carotid artery. A single autologous blood clot was injected into the left internal carotid artery through the catheter. The brain distribution of [1-11C]octanoate and cerebral blood flow (CBF) were determined 24 h after insult using a high resolution PET scanner. Post mortem brain regions unstained with 2,3,5-triphenyltetrazolium chloride (TTC) were defined as infarcts. In the region of an infarct, accumulation of [1-11C]octanoate decreased concurrently with CBF reduction. In contrast, normal accumulation of [1-11C]octanoate was observed in ischemic but vital regions, suggesting that an increased accumulation of [1-11C]octanoate relative to CBF takes place in these regions. In conclusion, [1-11C]octanoate accumulated in ischemic but vital regions, indicating that [1-11C]octanoate is a potentially useful PET tracer for imaging and evaluating the pathophysiology of ischemic stroke.
authors.affiliation: Institute for Biofunctional Research Co., Inc., Osaka, Japan. kuge@med.hokudai.ac.jp
authors.forename: Y
authors.initials: Y
authors.lastname: Kuge
authors.forename: H
authors.initials: H
authors.lastname: Kawashima
authors.forename: K
authors.initials: K
authors.lastname: Minematsu
authors.forename: Y
authors.initials: Y
authors.lastname: Hasegawa
authors.forename: T
authors.initials: T
authors.lastname: Yamaguchi
authors.forename: Y
authors.initials: Y
authors.lastname: Miyake
authors.forename: T
authors.initials: T
authors.lastname: Hashimoto
authors.forename: M
authors.initials: M
authors.lastname: Imanishi
authors.forename: M
authors.initials: M
authors.lastname: Shiomi
authors.forename: N
authors.initials: N
authors.lastname: Tamaki
authors.forename: N
authors.initials: N
authors.lastname: Hashimoto
mesh_terms: D000818:Animals; D002210:Caprylates; D002560:Cerebrovascular Circulation; D004195:Disease Models, Animal; D004285:Dogs; D008297:Male; D019275:Radiopharmaceuticals; D013923:Thromboembolism / Q000000981:diagnostic imaging*; D014055:Tomography, Emission-Computed
chemical_list: D002210:Caprylates; D019275:Radiopharmaceuticals; C031492:octanoic acid