[Impairment of benzodiazepine receptor in Parkinson's disease evaluated by 123I-iomazenil SPECT].
123I-iomazenil is a partial inverse agonist of central-type benzodiazepine receptor (BZR). Single photon emission tomography (SPECT) using 123I-iomazenil was performed in 15 patients with Parkinson's disease (PD). SPECT images were obtained 3 hours after intravenous injection of 167 MBq of 123I-iomazenil. The ratio of 123I-iomazenil SPECT count in the cerebral cortex to that in the cerebellum was calculated as the binding potential index (BPI). The BPIs in the lower frontal, temporal, parietal and occipital cortices correlated with the motor disability evaluated by Yahr's stage. The BPI in the upper frontal cortex showed the same tendency as in the other regions but did not reach a significant level. These results suggest that BZR in the cerebral cortex of patients with PD may be impaired in proportion to the severity of the disease and that 123I-iomazenil SPECT is useful for evaluating the pathophysiological condition in PD.
Kawabata
K
K
Fifth Department of Internal Medicine, Hyogo College of Medicine, Nishinomiya, Japan.
Tachibana
H
H
Sugita
M
M
Fukuchi
M
M
D000368:Aged; D000369:Aged, 80 and over; D002540:Cerebral Cortex / Q000378:metabolism*; D005260:Female; D005442:Flumazenil / Q000031:analogs & derivatives*; D006801:Humans; D007457:Iodine Radioisotopes; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000000981:diagnostic imaging* / Q000378:metabolism; D011963:Receptors, GABA-A / Q000378:metabolism*; D015899:Tomography, Emission-Computed, Single-Photon
D007457:Iodine Radioisotopes; D011963:Receptors, GABA-A; D005442:Flumazenil; C063038:iomazenil