Sisson J C, Lynch J J, Johnson J, Jaques S, Wu D, Bolgos G, Lucchesi B R, Wieland D M
University of Michigan Medical Center, Department of Internal Medicine (Nuclear Medicine), Ann Arbor 48109-0028.
Am Heart J. 1988 Jul;116(1 Pt 1):67-76. doi: 10.1016/0002-8703(88)90251-7.
Experiments were designed to detect regional disruptions of adrenergic neurons in the hearts of living dogs. The neuron disruption was achieved by the application of phenol to the epicardium of the left ventricle. Evidence for denervation was the reduction in endogenous norepinephrine (NE) concentrations in the myocardium beneath the region of phenol treatment and toward the apex. Radiolabeled meta-iodobenzylguanidine (MIBG) acts as an analog of NE and as such is concentrated in adrenergic nerve terminals. Following phenol application, MIBG labeled with 125I was found, 20 hours after injection, to be distributed within myocardium in patterns comparable to those of NE. However, left stellectomy did not alter the distributions of NE or 125I-MIBG in the myocardium and apparently did not disrupt adrenergic innervation. MIBG labeled with 123I enabled scintigraphic images of heart neurons in the living dog 3 and 20 hours after injection; these images portrayed the regions of adrenergic neuron disruption caused by phenol treatment. Concentrations of thallium-201 depicted on scintigraphic image and of triphenyltetrazolium observed on in vitro staining demonstrated no myocardial injury. Thus scintigraphy with 123I-MIBG will display regional adrenergic denervations in the heart.
实验旨在检测活体犬心脏中肾上腺素能神经元的局部破坏情况。通过将苯酚应用于左心室心外膜来实现神经元破坏。去神经的证据是苯酚处理区域下方及向心尖方向的心肌中内源性去甲肾上腺素（NE）浓度降低。放射性标记的间碘苄胍（MIBG）作为NE的类似物，因此集中在肾上腺素能神经末梢。应用苯酚后，注射后20小时发现，用125I标记的MIBG在心肌中的分布模式与NE相似。然而，左星状神经节切除术并未改变心肌中NE或125I-MIBG的分布，显然也未破坏肾上腺素能神经支配。用123I标记的MIBG在注射后3小时和20小时能够对活体犬心脏神经元进行闪烁显像；这些图像描绘了苯酚处理引起的肾上腺素能神经元破坏区域。闪烁显像图上显示的铊-201浓度以及体外染色观察到的三苯基四氮唑表明没有心肌损伤。因此，用123I-MIBG进行闪烁显像将显示心脏中的局部肾上腺素能去神经支配情况。
