Kawabata K, Tachibana H
Fifth Department of Internal Medicine, Hyogo College of Medicine.
Nihon Rinsho. 1997 Jan;55(1):244-8.
123I-iomazenil is a partial inverse agonist of central-type benzodiazepine receptors (BZRs). BZR and the gamma-aminobutylic acid(GABA) receptor comprise a receptor complex in the cerebral cortex. Therefore, 123I-iomazenil SPECT will provide indirect information of the GABA receptor. Since the GABA-ergic system has been reported to modulate the dopaminergic system, the impairment of GABA/BZR may affect parkinsonian symptoms. However, there are few reports on Parkinson's disease(PD) regarding the impairment of GABA/BZR in the cerebral cortex. We found a correlation between motor disability and decrease in 123I-iomazenil uptake in the cerebral cortex, suggesting that BZR in the cerebral cortex of patients with PD may be impaired in proportion to the severity of the disease. In addition, the 123I-iomazenil image is, in part, different from the perfusion image. Therefore, 123I-iomazenil SPECT may give an additional information on the pathophysiology of PD.
123I-碘美西泮是中枢型苯二氮䓬受体（BZR）的部分反向激动剂。BZR与γ-氨基丁酸（GABA）受体在大脑皮层中构成一个受体复合物。因此，123I-碘美西泮单光子发射计算机断层扫描（SPECT）将提供GABA受体的间接信息。由于据报道GABA能系统可调节多巴胺能系统，GABA/BZR的损害可能会影响帕金森症状。然而，关于大脑皮层中GABA/BZR损害与帕金森病（PD）的报道很少。我们发现运动功能障碍与大脑皮层中123I-碘美西泮摄取减少之间存在相关性，这表明PD患者大脑皮层中的BZR可能会随着疾病严重程度而受损。此外，123I-碘美西泮图像在一定程度上与灌注图像不同。因此，123I-碘美西泮SPECT可能会为PD的病理生理学提供额外信息。
