Autor: |
Hall, H., Halldin, C., Dijkstra, Durk, Wikström, Håkan, Wise, Lawrence D., Pugsley, Thomas A., Sokoloff, Pierre, Pauli, Stefan, Farde, Lars, Sedvall, Göran |
Předmět: |
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Zdroj: |
Psychopharmacology; 1996, Vol. 128 Issue 3, p240, 8p |
Abstrakt: |
The selective D[sub 3] -dopamine receptor agonist 4aR,10bR-(+)-trans-3,4,4a,10b-tetrahydro-4-[N-propyl-2,3-[sup 3] H]-2H,5H-[1]benzopyrano[4,3-b]-1,4-oxazin-9-ol ([[sup 3] H]PD 128907) was used to visualise D[sub 3] -dopamine receptors in whole hemisphere cryosections from post-mortem human brain. [[sup 3] H]PD 128907 has an 18- to 40-fold selectivity for D[sub 3] - over D[sub 2] -dopamine receptors as compared to a 7- to 24-fold selectivity of the more commonly used ligand [[sup 3] H]7-OH-DPAT. [[sup 3] H]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 [[sup 3] H]PD 128907 was specifically bound, as judged from the low binding remaining in the presence of the D[sub 2] /D[sub 3] -dopamine receptor antagonist raclopride. This gives the ligand a potential for the detection of low density D[sub 3] -dopamine receptors in the human brain. The binding obtained with [[sup 3] H]PD 128907 was qualitatively similar to that using [[sup 3] H]7-OH-DPAT in the presence of GTP. However, [[sup 3] H]7-OH-DPAT labelled, in contrast to [[sup 3] H]PD 128907, also D[sub 3] -dopamine receptors in neocortex. The new compound [[sup 3] H]PD 128907 appears to be a suitable radioligand for autoradiographic examination of the D[sub 3] -dopamine receptor localisation in the human brain, and should also be useful for pharmacological studies of this receptor subtype. [ABSTRACT FROM AUTHOR] |
Databáze: |
Complementary Index |
Externí odkaz: |
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