Visualization of mitochondrial oxygen fixation in brain slices by gas-tissue autoradiography.
We have developed a novel autoradiographic method of visualizing oxygen fixation with sufficient delivery of [(15)O]O(2)/O(2). Brain slices (400 microm) were preincubated in Krebs-Ringer phosphate buffer and exposed to [(15)O]O(2) in a chamber. Fixation of [(15)O]O(2) correlated with the polarographically measured oxygen consumption among tissue slices from various organs (r=0.84). The fixation of [(15)O]O(2) by brain slices was significantly reduced (7. 2% of the control) by heat-treatment or dose dependently by NaCN (18. 2% of the control on 50 mM NaCN pretreatment). The (15)O radioactivity in the brain slices prepared from rotenone injected rats was also reduced compared to the control (56.8% of the control side). In an autoradiographic study, (15)O radioactivity showed a heterogeneous distribution both in coronal and sagittal sections. Autoradiography of young and senescent rat brain sections showed reduction of oxygen uptake with aging in the cerebrum, the senescent being 77.4% of the young. This method provides information regarding basic oxygen consumption of tissue slices under condition of sufficient O(2) delivery, which reflects mitochondrial electron transport.
Positron Medical Center, Tokyo Metropolitan Institute of Gerontology, Sakae-cho, Itaboshi-ku, Tokyo 173-0015, Japan. sasaki@pet.tmig.or.jp
T
T
Sasaki
S
S
Soga
S
S
Ishii
T
T
Kobayashi
H
H
Nagai
M
M
Senda
D000375:Aging / Q000502:physiology; D000818:Animals; D001345:Autoradiography; D001921:Brain / Q000187:drug effects / Q000378:metabolism*; D004579:Electron Transport; D004734:Energy Metabolism / Q000502:physiology; D066298:In Vitro Techniques; D008297:Male; D008928:Mitochondria / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption / Q000502:physiology; D010104:Oxygen Radioisotopes; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism; D012402:Rotenone / Q000494:pharmacology; D014055:Tomography, Emission-Computed
D010104:Oxygen Radioisotopes; D017382:Reactive Oxygen Species; D012402:Rotenone; D010100:Oxygen