The effect of dopamine agonist therapy on dopamine transporter imaging in Parkinson's disease

Mov Disord. 1999 Nov;14(6):940-6. doi: 10.1002/1531-8257(199911)14:6<940::aid-mds1005>;2-y.


Single-photon emission computed tomography (SPECT) imaging with the dopamine transporter ligand, [123I] beta-CIT (2beta-carboxymethoxy-3beta-[4-iodophenyl] tropane), has been proposed as a means of measuring Parkinson's disease (PD) progression. To be useful in this role, however, [123I] beta-CIT imaging should not be influenced by the medications used to treat PD, including the dopamine agonist drugs such as pergolide. We assessed the effect of adjunctive pergolide administration on [123I] beta-CIT uptake in 12 patients with PD, who were being treated with levodopa, initiating pergolide therapy for motor fluctuations. Patients underwent [123I] beta-CIT imaging at baseline, subsequently while on pergolide therapy (6 weeks), and again 4 weeks after pergolide wash-out. Uptake in the striatum was averaged for the two sides and expressed as (striatum - occipital)/occipital, with similar calculations for putamen and caudate. Consistent with PD, the patients' mean striatal and putamen uptake ratios at baseline were significantly less (p <0.001) than the mean values from 26 normal control subjects of similar age. During pergolide treatment, the striatal and putamen [123I] beta-CIT uptake ratios were each statistically similar to baseline, although there was a slight trend toward an increased striatal value (8% higher on pergolide; p = 0.105). Caudate [123I] beta-CIT uptake was 11% higher on pergolide therapy (nominal p = 0.042, but not significant when adjusted for multiple comparisons: p = 0.126). After pergolide wash-out, the striatal, putamen, and caudate uptake ratios did not differ from baseline. Therefore, we found that pergolide therapy did not significantly affect [123I] beta-CIT SPECT imaging but we cannot exclude a small influence.

Publication types

  • Clinical Trial

MeSH terms

  • Aged
  • Brain / diagnostic imaging
  • Brain / drug effects*
  • Brain Mapping
  • Carbidopa / administration & dosage
  • Carbidopa / adverse effects
  • Carrier Proteins / drug effects*
  • Carrier Proteins / metabolism
  • Cocaine / analogs & derivatives
  • Corpus Striatum / diagnostic imaging
  • Corpus Striatum / drug effects
  • Dopamine Agonists / administration & dosage*
  • Dopamine Agonists / adverse effects
  • Dopamine Plasma Membrane Transport Proteins
  • Dose-Response Relationship, Drug
  • Drug Administration Schedule
  • Drug Combinations
  • Drug Therapy, Combination
  • Female
  • Humans
  • Iodine Radioisotopes
  • Levodopa / administration & dosage
  • Levodopa / adverse effects
  • Male
  • Membrane Glycoproteins*
  • Membrane Transport Proteins*
  • Middle Aged
  • Motor Skills / drug effects
  • Nerve Tissue Proteins*
  • Parkinson Disease / diagnostic imaging
  • Parkinson Disease / drug therapy*
  • Pergolide / administration & dosage*
  • Pergolide / adverse effects
  • Putamen / diagnostic imaging
  • Putamen / drug effects
  • Tomography, Emission-Computed, Single-Photon*


  • Carrier Proteins
  • Dopamine Agonists
  • Dopamine Plasma Membrane Transport Proteins
  • Drug Combinations
  • Iodine Radioisotopes
  • Membrane Glycoproteins
  • Membrane Transport Proteins
  • Nerve Tissue Proteins
  • carbidopa, levodopa drug combination
  • Pergolide
  • Levodopa
  • 2beta-carbomethoxy-3beta-(4-iodophenyl)tropane
  • Cocaine
  • Carbidopa