Decrease of D2 receptors indicated by 123I-iodobenzamide single-photon emission computed tomography relates to neurological deficit in treated Wilson's disease.
Single-photon emission computed tomography with 123I-iodobenzamide, a dopamine D2 receptor antagonist, was employed to study dopamine D2 receptor densities in 17 patients with biochemically proved Wilson's disease and stable neurological status with therapy and in 5 age-matched control subjects. Of the 17 patients with Wilson's disease, 5 were neurologically asymptomatic, 3 had cerebellar signs, 1 exhibited a mild parkinsonian syndrome, 7 showed a parkinsonian syndrome and cerebellar signs, and 1 had generalized dystonia and a parkinsonian syndrome. In 5 age-matched control subjects specific isotope binding as calculated by the basal ganglia to frontal cortex ratio was 1.57 +/- 0.04 (mean +/- standard deviation). The ratio in patients with Wilson's disease ranged from 1.56 +/- 0.05 (n = 5, asymptomatic patients) to 1.17 +/- 0.02 (n = 4, marked neurological impairment). We observed an almost linear correlation between the reduction of 123I-iodobenzamide (IBZM) binding and the severity of neurological signs at the time of IBZM-SPECT (correlation coefficient, -0.84; p < 0.01). We suggest that the reduction of postsynaptic striatal dopamine D2 receptors as detected by IBZM-SPECT reflects striatal neuronal damage in Wilson's disease.
Oertel
W H
WH
Department of Neurology, Klinikum Grosshadern, Ludwig-Maximilians-University, Federal Republic of Germany.
Tatsch
K
K
Schwarz
J
J
Kraft
E
E
Trenkwalder
C
C
Scherer
J
J
Weinzierl
M
M
Vogl
T
T
Kirsch
C M
CM
D000293:Adolescent; D000328:Adult; D001479:Basal Ganglia / Q000378:metabolism; D001549:Benzamides; D065127:Dopamine D2 Receptor Antagonists; D006527:Hepatolenticular Degeneration / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000503:physiopathology; D006801:Humans; D007457:Iodine Radioisotopes; D011759:Pyrrolidines; D017448:Receptors, Dopamine D2 / Q000378:metabolism*; D015899:Tomography, Emission-Computed, Single-Photon
D001549:Benzamides; D065127:Dopamine D2 Receptor Antagonists; D007457:Iodine Radioisotopes; D011759:Pyrrolidines; D017448:Receptors, Dopamine D2; C055743:3-iodo-2-hydroxy-6-methoxy-N-((1-ethyl-2-pyrrolidinyl)methyl)benzamide