Estimation of oxygen metabolism in a rat model of permanent ischemia using positron emission tomography with injectable15O-O2.
The threshold of cerebral blood flow (CBF) into infarction in rats has been indicated to be similar to that in patients. However, CBF does not reflect metabolic function, and so estimations of oxygen metabolism have been required. Here, we estimated changes in oxygen metabolism after occluding the right middle cerebral artery (MCA) in rats using an injectable (15)O-O(2) we developed. A decrease in CBF (left: 0.67+/-0.22 mL/min/g, right: 0.44+/-0.17 mL/min/g, P<0.05) and compensatory increase in the oxygen extraction fraction (OEF) (left: 0.42+/-0.13, right: 0.50+/-0.19, P<0.05) were observed at 1-h after occlusion. In contrast, a marked decrease in CBF and the cerebral metabolic rate for oxygen and a collapse of the compensatory OEF mechanism were found at 24 h after occlusion. Injectable (15)O-O(2) could be used to reliably estimate oxygen metabolism in an infarction rat model with positron emission tomography.
Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, Japan.
Takashi
T
Temma
Yasuhiro
Y
Magata
Yuji
Y
Kuge
Sayaka
S
Shimonaka
Kohei
K
Sano
Yumiko
Y
Katada
Hidekazu
H
Kawashima
Takahiro
T
Mukai
Hiroshi
H
Watabe
Hidehiro
H
Iida
Hideo
H
Saji
D000818:Animals; D002545:Brain Ischemia / Q000000981:diagnostic imaging / Q000378:metabolism*; D002536:Cerebral Arteries / Q000000981:diagnostic imaging; D002560:Cerebrovascular Circulation; D004195:Disease Models, Animal; D008297:Male; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption; D010104:Oxygen Radioisotopes / Q000494:pharmacology; D049268:Positron-Emission Tomography / Q000379:methods; D011859:Radiography; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
D010104:Oxygen Radioisotopes; D010100:Oxygen