Characterization of sulpiride-displaceable 3H-YM-09151-2 binding sites in rat frontal cortex and the effects of subchronic treatment with haloperidol on cortical D-2 dopamine receptors.
We investigated the pharmacological properties of the sulpiride-displaceable binding sites labeled by 3H-YM-09151-2 in rat frontal cortex, compared to those in striatum. The IC50 value of ketanserin was 486 nM, which was apparently different from its affinity for the 5HT-2 receptor. Various dopamine antagonists showed almost the same inhibitory effects for binding site in frontal cortex and striatum. Sulpiride-displaceable 3H-YM-09151-2 binding sites were considered to be D-2 dopamine receptors. After subchronic treatment with haloperidol, the D-2 receptor density of frontal cortex (0.55 fmol/mg tissue) increased to the same extent (about 25%) as striatum without significant change in apparent affinity.
Department of Psychiatry, Saitama Medical School, Japan.
T
T
Kazawa
M
M
Mikuni
T
T
Higuchi
I
I
Arai
K
K
Takahashi
T
T
Yamauchi
D000818:Animals; D001549:Benzamides / Q000378:metabolism* / Q000494:pharmacology; D001665:Binding Sites; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism*; D018492:Dopamine Antagonists; D005625:Frontal Lobe / Q000187:drug effects / Q000378:metabolism*; D006220:Haloperidol / Q000494:pharmacology*; D066298:In Vitro Techniques; D007650:Ketanserin / Q000494:pharmacology; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D011954:Receptors, Dopamine / Q000187:drug effects* / Q000378:metabolism; D013469:Sulpiride / Q000494:pharmacology
D001549:Benzamides; D018492:Dopamine Antagonists; D011954:Receptors, Dopamine; D013469:Sulpiride; D007650:Ketanserin; D006220:Haloperidol; C030265:nemonapride