Alterations of striatal dopamine D2 receptors contribute to deteriorated response to L-dopa in Parkinson's disease: a [123I]-IBZM SPET study.
Single photon emission tomography with the ligand [123I]-IBZM was used to image central dopamine D2 receptors in Parkinson's disease patients. The aim was to assess striatal receptor densities in relation to response to L-Dopa therapy. In the parkinsonian patients group who were untreated until SPET study and in the group of patients with a sustained response to chronic L-Dopa, striatal [123I]-IBZM uptake did not differ significantly from mean values of the control group. On the contrary, significantly diminished uptake of [123I]-IBZM was found in the basal ganglia regions of the group of patients who developed a complicated/fluctuating response to chronic L-Dopa treatment. Our results indicate that striatal D2 receptor alterations in Parkinson's disease may contribute to the altered response to L-Dopa.
Pizzolato
G
G
Department of Neurology, University of Padova School of Medicine, Italy.
Chierichetti
F
F
Rossato
A
A
Cagnin
A
A
Fabbri
M
M
Dam
M
M
Ferlin
G
G
Battistin
L
L
D000328:Adult; D000368:Aged; D000978:Antiparkinson Agents / Q000494:pharmacology*; D001549:Benzamides; D016022:Case-Control Studies; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism; D015259:Dopamine Agents / Q000494:pharmacology*; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes; D007980:Levodopa / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000000981:diagnostic imaging / Q000378:metabolism*; D011759:Pyrrolidines; D017448:Receptors, Dopamine D2 / Q000187:drug effects* / Q000378:metabolism; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
D000978:Antiparkinson Agents; D001549:Benzamides; D015259:Dopamine Agents; D007457:Iodine Radioisotopes; D011759:Pyrrolidines; D017448:Receptors, Dopamine D2; D007980:Levodopa; C055743:3-iodo-2-hydroxy-6-methoxy-N-((1-ethyl-2-pyrrolidinyl)methyl)benzamide