Hoff S J, Stewart J R, Frist W H, Kessler R M, Sandler M P, Atkinson J B, Votaw J, Carey J A, Ansari M S, Merrill W H
Department of Cardiac and Thoracic Surgery, Vanderbilt University Medical Center, Nashville, Tennessee.
Ann Thorac Surg. 1992 Apr;53(4):572-7. doi: 10.1016/0003-4975(92)90313-s.
Positron emission tomography has recently been used to evaluate ischemic heart disease through changes in myocardial blood flow and carbohydrate metabolism. Positron-emitting tracers were evaluated for their ability to detect acute allograft rejection after heterotopic cardiac transplantation in the rat. Sham-operated controls, nonrejecting isografts, and rejecting allografts were evaluated. Decay-corrected uptake of 13NH3 and 18F 2-fluoro 2-deoxyglucose (FDG) reflects blood flow and glucose flux, respectively. Histologic examination of rejecting allografts documented mild rejection at 4 days and severe acute rejection by 8 days. All isografts were free from rejection. Uptake of FDG is greater in rejecting allografts than in nonrejecting isografts during both severe rejection (2.4% +/- 0.8% versus 0.7% +/- 0.4%; p less than 0.02) and mild rejection (2.1% +/- 0.6% versus 0.4% +/- 0.1%; p less than 0.02). Uptake of NH3 in severely rejected grafts is reduced compared with nonrejecting grafts (0.6% +/- 0.3% versus 1.7% +/- 1.1%; p less than 0.02). There is no difference in NH3 uptake during mild rejection (1.8% +/- 0.7% versus 1.3% +/- 0.3%; p greater than 0.05). Uptake of FDG and NH3 in native hearts of animals from all experimental groups is not significantly different from that in sham-operated controls. Glucose may be a preferred metabolic substrate during rejection. Our data support a humoral mechanism for substrate preference during transplant rejection and a potential diagnostic role for positron emission tomography.
正电子发射断层扫描术最近已被用于通过心肌血流和碳水化合物代谢的变化来评估缺血性心脏病。对正电子发射示踪剂检测大鼠异位心脏移植后急性同种异体移植排斥反应的能力进行了评估。对假手术对照组、未发生排斥反应的同基因移植组和发生排斥反应的同种异体移植组进行了评估。经衰变校正的¹³NH₃和¹⁸F 2-氟-2-脱氧葡萄糖（FDG）摄取分别反映血流和葡萄糖通量。对发生排斥反应的同种异体移植组织进行组织学检查，结果显示4天时为轻度排斥反应，8天时为严重急性排斥反应。所有同基因移植均未发生排斥反应。在严重排斥反应期间（2.4%±0.8%对0.7%±0.4%；p<0.02）和轻度排斥反应期间（2.1%±0.6%对0.4%±0.1%；p<0.02），发生排斥反应的同种异体移植中FDG的摄取均高于未发生排斥反应的同基因移植。与未发生排斥反应的移植相比，严重排斥反应的移植中NH₃的摄取减少（0.6%±0.3%对1.7%±1.1%；p<0.02）。轻度排斥反应期间NH₃摄取无差异（1.8%±0.7%对1.3%±0.3%；p>0.05）。所有实验组动物的天然心脏中FDG和NH₃的摄取与假手术对照组相比无显著差异。在排斥反应期间，葡萄糖可能是一种更受青睐的代谢底物。我们的数据支持移植排斥反应期间底物偏好的体液机制以及正电子发射断层扫描术的潜在诊断作用。
