Shorr L D, Thompson R T, Marsh G D, Driedger A A, Magilligan D J
Department of Nuclear Medicine, Victoria Hospital, London, Ontario.
Can J Cardiol. 1991 Apr;7(3):155-60.
Factors that limit survival of explanted cardiac allografts include intracellular acidosis and loss of high energy phosphates. This study was undertaken to determine if these processes could be retarded by specific interventions during organ storage and to determine the capabilities of phosphorus-31 (31P) nuclear magnetic resonance spectroscopy to monitor these intracellular changes noninvasively. Thirty-six excised rabbit hearts were studied in six groups according to the storage temperature and conditions of their perfusion: nonperfused, aerated perfusate or oxygenated perfusate, each at 4 degrees C and 20 degrees C. 31P spectra were continuously obtained starting 20 mins post explanation and continuing for at least 5 h. The resulting data were analyzed to determine metabolite concentration and intracellular pH. The phosphodiesters, inorganic phosphates and phosphomonoesters, as well as the phosphocreatine and adenosine triphosphate peaks, could be reproducibly resolved. Comparisons at 0.5, 1, 2, 3, 4, and 5 h indicated that high energy phosphates were the most quickly degraded, and intracellular acidosis progressed most rapidly in nonperfused hearts at 20 degrees C. Hearts perfused with oxygenated cardioplegic solution at 4 degrees C showed significantly prolonged preservation of high energy phosphates and delayed development of intracellular acidosis. It was concluded that continuous infusion of oxygenated cardioplegic solution improves preservation of high energy phosphates at low temperatures, and that 31P magnetic resonance spectroscopy can be used to monitor these important intracellular changes rapidly and nonivasively, permitting serial studies on the same heart. This technique substantially reduced the number of animals needed for the study (36 were used in this study rather than the 216 required by traditional techniques).
限制移植心脏同种异体移植物存活的因素包括细胞内酸中毒和高能磷酸盐的丧失。本研究旨在确定在器官保存期间，这些过程是否可以通过特定干预措施得到延缓，并确定磷-31（³¹P）核磁共振波谱技术在无创监测这些细胞内变化方面的能力。根据保存温度和灌注条件，将36个离体兔心脏分为六组进行研究：非灌注组、充氧灌注液组或氧合灌注液组，每组分别置于4℃和20℃环境。从心脏离体后20分钟开始持续获取³¹P波谱，至少持续5小时。对所得数据进行分析，以确定代谢物浓度和细胞内pH值。磷酸二酯、无机磷酸盐和磷酸单酯，以及磷酸肌酸和三磷酸腺苷峰均可重复分辨。在0.5、1、2、3、4和5小时进行的比较表明，高能磷酸盐降解最快，在20℃下非灌注心脏的细胞内酸中毒进展最为迅速。4℃下用氧合心脏停搏液灌注的心脏，其高能磷酸盐的保存时间显著延长，细胞内酸中毒的发展也有所延迟。研究得出结论，持续输注氧合心脏停搏液可改善低温下高能磷酸盐的保存，³¹P磁共振波谱技术可用于快速、无创地监测这些重要的细胞内变化，从而能够对同一心脏进行系列研究。该技术大幅减少了研究所需的动物数量（本研究使用了36只动物，而传统技术需要216只）。
