Differential effects of stress on [¹¹C]raclopride and [¹¹C]MNPA binding to striatal D₂/D₃ dopamine receptors: a PET study in conscious monkeys

Synapse. 2011 Jan;65(1):84-9. doi: 10.1002/syn.20845.


It has been reported that stress and facilitation of dopamine neuronal system are closely related. In the present study, the effects of stress on the binding of antagonist-based [¹¹C]raclopride and agonist-based (R)-2-CH3O-N-n- propylnorapomorphine ([¹¹C]MNPA) to D₂/D₃ receptors were evaluated in the striatum of conscious monkey brain. The stress state assessed from plasma cortisol level was negatively correlated with [¹¹C]raclopride binding as expected. It was noteworthy that [¹¹C]MNPA binding exhibited a positive correlation with stress state; thus, the animals with higher cortisol levels showed higher binding to D₂/D₃ receptors.

MeSH terms

  • Animals
  • Apomorphine / metabolism*
  • Apomorphine / pharmacology
  • Brain / diagnostic imaging
  • Brain / drug effects
  • Brain / metabolism
  • Carbon Radioisotopes / metabolism*
  • Carbon Radioisotopes / pharmacology
  • Hydrocortisone / blood
  • Macaca mulatta
  • Male
  • Positron-Emission Tomography
  • Raclopride / metabolism*
  • Raclopride / pharmacology
  • Receptors, Dopamine D2 / metabolism*
  • Receptors, Dopamine D3 / metabolism*
  • Stress, Physiological / physiology*


  • Carbon Radioisotopes
  • Receptors, Dopamine D2
  • Receptors, Dopamine D3
  • Raclopride
  • Apomorphine
  • Hydrocortisone