Reduced striatal dopaminergic innervation shown by IPT and SPECT in patients under neuroleptic treatment: need for levodopa therapy? Academic Article uri icon



  • We investigated the availability of dopamine reuptake sites in the striata of two patients with productive symptoms and neuroleptic therapy as well as progressive parkinsonism using the new dopamine transporter ligand [123I]N-(3-iodopropen-2-yl)-2beta-carbo-methoxy-3beta- (4-chlorophenyl)tropane (IPT) and single photon emission computed tomography (SPECT). Normal specific binding in the caudate nucleus was 8.6 +/- 1.2 and in the putamen 6.5 +/- 1.3 (mean +/- S.D.; n = 8; mean age, 56.7 years; range 41-67 years). Patient 1 (age 43) was admitted to our clinic at age 38 because of left-sided parkinsonism. At age 40, she developed paranoid psychosis without change after cessation of L-DOPA and lisuride treatment for 3 months. She was diagnosed as a schizophrenic, paranoid subtype (DSM-III-R). IPT-SPECT showed a loss of dopaminergic nerve terminals (right caudate/putamen, 5.16/2.0; left caudate/putamen, 5.92/2.66). Patient 2 (age, 61 years) had a history of paranoid psychosis for approx. 30 years. He experienced progressive right-sided parkinsonism since age 57 when treated with clozapine. IPT-SPECT showed a marked reduction of striatal dopamine transporter binding (right caudate/putamen, 5.06/1.65; left caudate/putamen, 3.8/1.12). Our findings indicate that patients may suffer contemporaneously from Parkinson's disease and schizophrenia. In these patients, the proof of a nigrostriatal dopaminergic deficit justifies treatment with neuroleptics and dopaminergic drugs. Imaging of dopamine transporters with SPECT and IPT or a related compound represents an attractive alternative to the more complex measurements of fluorodopa uptake with positron emission tomography (PET).

publication date

  • July 15, 1998



  • Antipsychotic Agents
  • Dopamine
  • Iodine Radioisotopes
  • Neostriatum
  • Parkinson Disease
  • Schizophrenia, Paranoid
  • Tomography, Emission-Computed, Single-Photon
  • Tropanes


Scopus Document Identifier

  • 0032528444

PubMed ID

  • 9754702

Additional Document Info


  • 83


  • 1