Detection of Cardiomyocyte Death in a Rat Model of Ischemia and Reperfusion Using 99mTc-Labeled Annexin V

Journal of Nuclear Medicine

Atsuhiro Kawashima¹  Takahiro Higuchi¹  Akira Muramori¹  Norihisa Tonami¹  Seigo Kinuya¹  Kenichi Nakajima¹  Ichiro Matsunari¹  Jonathan F. Tait¹  H. William Strauss¹  Junichi Taki¹ 

关键词: ^99mTc-annexin V;    ischemia;    reperfusion;    apoptosis;   

DOI  :  

学科分类：医学（综合）

来源: Society of Nuclear Medicine

【 摘 要 】

There is increasing evidence that cell death after myocardial ischemia and reperfusion may begin as apoptosis rather than necrosis. To determine the time course, location, and extent of this process, we studied groups of rats after a 20-min interval of coronary occlusion and reperfusion. Methods: After thoracotomy, the left coronary artery was occluded for 20 min. After release and before study, groups of animals were allowed to recover for various intervals: 0.5 h (n = 6), 1.5 h (n = 7), 6 h (n = 7), 1 d (n = 8), 3 d (n = 8), or 2 wk (n = 5). At the time of study, the rats were injected with 99mTc-annexin V (80–150 MBq). One hour later, to verify the area at risk, 201Tl (0.74 MBq) was injected intravenously just after the left coronary artery reocclusion and the rats were sacrificed 1 min later. Dual-tracer autoradiography was performed to assess 99mTc-annexin V uptake and the area at risk. Results: Extensive 99mTc-annexin V uptake was observed in the mid myocardium after 0.5–1.5 h of reperfusion. The area of annexin uptake had expanded in the subendocardial and subepicardial layers at 6 h after reperfusion and then gradually lessened over 3 d. At 0.5 and 1.5 h of reperfusion, 99mTc-annexin V uptake ratios were 7.36 ± 2.95 and 6.34 ± 2.24 (mean ± SD), respectively. The uptake ratios gradually decreased at 6 h, 1 d, 3 d, and 2 wk after reperfusion (4.65 ± 1.93, 3.27 ± 0.92 [P < 0.01 vs. 0.5 h], 1.84 ± 0.55 [P < 0.001 vs. 0.5 h, P < 0.005 vs. 1.5 h], and 1.65 ± 0.31 [P < 0.001 vs. 0.5 h, P < 0.005 vs. 1.5 h], respectively). Conclusion: These data indicate that annexin binding commences soon after ischemia and reperfusion in the mid myocardium within the area at risk and expands to include the subendocardial and subepicardial layers at 6 h after reperfusion, followed by gradual reduction of activity over 3 d.

【 授权许可】

Unknown