TY - JOUR
T1 - Detection of viable cortical neurons using benzodiazepine receptor imaging after reversible focal ischaemia in rats
T2 - Comparison with regional cerebral blood flow
AU - Watanabe, Yoshiyuki
AU - Nakano, Takayuki
AU - Yutani, Kenji
AU - Nishimura, Hiroshi
AU - Kusuoka, Hideo
AU - Nakamura, Hironobu
AU - Nishimura, Tsunehiko
N1 - Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2000
Y1 - 2000
N2 - To elucidate the utility of benzodiazepine receptor imaging for the detection of viable cortical neurons, dual-tracer autoradiography using iodine-125 iomazenil (IMZ) and iodine-123 N-isopropyl-4-iodoamphetamine (IMP) was performed in a model of reversible focal ischaemia during the acute and subacute phases. The right middle cerebral artery of anaesthetized rats was occluded for 60 min using an intraluminal filament and reperfused. In the acute phase study, 125I-IMZ (370 kBq) was injected via the femoral vein at 2 h after reperfusion, and 123I-IMP (37 MBq) was injected at 50 min post- injection. Rats were sacrificed 10 min after the injection of 123I-IMP. In the subacute phase study, the same procedure was performed at 5 days after reperfusion. In the acute phase, the IMP uptake was significantly decreased in almost all areas of the lesioned hemisphere, an exception being the cerebellum; however, the IMZ uptake was significantly decreased only in ischaemic cores. The discrepancy between IMZ and IMP uptake was observed in the lateral neocortex and the lateral caudate putamen (CPu), which were most frequently damaged in this ischaemic model. In the subacute phase, the IMZ uptake in lesioned rats was significantly decreased only in the parietal lobe and hippocampus, though the IMP uptake was decreased in many regions of lesioned hemispheres (the frontal, parietal cortex, CPu, hippocampus and thalamus). Histopathological findings indicated that both the IMP and the IMZ uptake was markedly decreased in necrotic areas. Although the IMP uptake was significantly decreased in the ischaemic areas, the IMZ uptake was maintained in these areas. These results suggest that benzodiazepine receptor imaging is superior to regional cerebral blood flow imaging for the detection of viable cortical neurons in both the acute and subacute phases of ischaemia.
AB - To elucidate the utility of benzodiazepine receptor imaging for the detection of viable cortical neurons, dual-tracer autoradiography using iodine-125 iomazenil (IMZ) and iodine-123 N-isopropyl-4-iodoamphetamine (IMP) was performed in a model of reversible focal ischaemia during the acute and subacute phases. The right middle cerebral artery of anaesthetized rats was occluded for 60 min using an intraluminal filament and reperfused. In the acute phase study, 125I-IMZ (370 kBq) was injected via the femoral vein at 2 h after reperfusion, and 123I-IMP (37 MBq) was injected at 50 min post- injection. Rats were sacrificed 10 min after the injection of 123I-IMP. In the subacute phase study, the same procedure was performed at 5 days after reperfusion. In the acute phase, the IMP uptake was significantly decreased in almost all areas of the lesioned hemisphere, an exception being the cerebellum; however, the IMZ uptake was significantly decreased only in ischaemic cores. The discrepancy between IMZ and IMP uptake was observed in the lateral neocortex and the lateral caudate putamen (CPu), which were most frequently damaged in this ischaemic model. In the subacute phase, the IMZ uptake in lesioned rats was significantly decreased only in the parietal lobe and hippocampus, though the IMP uptake was decreased in many regions of lesioned hemispheres (the frontal, parietal cortex, CPu, hippocampus and thalamus). Histopathological findings indicated that both the IMP and the IMZ uptake was markedly decreased in necrotic areas. Although the IMP uptake was significantly decreased in the ischaemic areas, the IMZ uptake was maintained in these areas. These results suggest that benzodiazepine receptor imaging is superior to regional cerebral blood flow imaging for the detection of viable cortical neurons in both the acute and subacute phases of ischaemia.
KW - Focal ischaemia
KW - Iodine- 125 iomazenil
KW - Iodine-123 N-isopropyl-4-iodoamphetamine
KW - Reperfusion
UR - http://www.scopus.com/inward/record.url?scp=0034028551&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0034028551&partnerID=8YFLogxK
U2 - 10.1007/s002590050038
DO - 10.1007/s002590050038
M3 - Article
C2 - 10774883
AN - SCOPUS:0034028551
SN - 0340-6997
VL - 27
SP - 308
EP - 313
JO - European Journal of Nuclear Medicine
JF - European Journal of Nuclear Medicine
IS - 3
ER -