Autoradiographic localisation of D3-dopamine receptors in the human brain using the selective D3-dopamine receptor agonist (+)-[3H]PD 128907

Psychopharmacology (Berl). 1996 Dec;128(3):240-7. doi: 10.1007/s002130050131.


The selective D3-dopamine receptor agonist 4aR, 10bR-(+)-trans-3,4,4a, 10b-tetrahydro-4-[N-propyl-2,3-3H]-2H,5H-[1] benzopyrano[4,3-b]-1,4-oxazin-9-ol ([3H]PD 128907) was used to visualise D3-dopamine receptors in whole hemisphere cryosections from post-mortem human brain. [3H]PD 128907 has an 18- to 40-fold selectivity for D3- over D2-dopamine receptors as compared to a 7- to 24-fold selectivity of the more commonly used ligand [3H]7-OH-DPAT. [3H]PD 128907 accumulated markedly in the nucleus accumbens and in the ventral parts of caudate nucleus and putamen, with a slightly heterogeneous (patch-matrix like) distribution. The binding in the lateral parts of caudate nucleus and putamen was much less dense. No binding was obtained in any other regions. A very high proportion of [3H]PD 128907 was specifically bound, as judged from the low binding remaining in the presence of the D2/D3-dopamine receptor antagonist raclopride. This gives the ligand a potential for the detection of low density D3-dopamine receptors in the human brain. The binding obtained with [3H]PD 128907 was qualitatively similar to that using [3H]7-OH-DPAT in the presence of GTP. However, [3H]7-OH-DPAT labelled, in contrast to [3H]PD 128907, also D3-dopamine receptors in neocortex. The new compound [3H]PD 128907 appears to be a suitable radioligand for autoradiographic examination of the D3-dopamine receptor localisation in the human brain, and should also be useful for pharmacological studies of this receptor subtype.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Autoradiography
  • Benzopyrans / analysis*
  • Benzopyrans / antagonists & inhibitors
  • Brain Chemistry*
  • Dopamine Agonists / analysis*
  • Dopamine Antagonists / pharmacology
  • Female
  • Guanosine Triphosphate / metabolism
  • Guanosine Triphosphate / pharmacology
  • Humans
  • Male
  • Middle Aged
  • Oxazines / analysis*
  • Oxazines / antagonists & inhibitors
  • Raclopride
  • Receptors, Dopamine / analysis*
  • Receptors, Dopamine / drug effects
  • Salicylamides / pharmacology
  • Tetrahydronaphthalenes / analysis*
  • Tetrahydronaphthalenes / antagonists & inhibitors


  • Benzopyrans
  • Dopamine Agonists
  • Dopamine Antagonists
  • Oxazines
  • Receptors, Dopamine
  • Salicylamides
  • Tetrahydronaphthalenes
  • 3,4,4a,10b-tetrahydro-4-propyl-2H,5H-(1)benzopyrano(4,3-b)-1,4-oxazin-9-ol
  • Raclopride
  • Guanosine Triphosphate
  • 7-hydroxy-2-N,N-dipropylaminotetralin