CHARACTERISTICS OF TETRAHYDROPROTOBERBERINES ON DOPAMINE D-1 AND D-2 RECEPTORS IN CALF STRIATUM

Citation
X. Guo et al., CHARACTERISTICS OF TETRAHYDROPROTOBERBERINES ON DOPAMINE D-1 AND D-2 RECEPTORS IN CALF STRIATUM, Zhongguo yaoli xuebao, 18(3), 1997, pp. 225-230
Citations number
13
Categorie Soggetti
Pharmacology & Pharmacy",Chemistry
Journal title
ISSN journal
02539756
Volume
18
Issue
3
Year of publication
1997
Pages
225 - 230
Database
ISI
SICI code
0253-9756(1997)18:3<225:COTODD>2.0.ZU;2-1
Abstract
AIM: To study the characteristics of tetrahydroprotoberberines (THPB) on dopamine D-1 and D-2 receptors and elucidate their structure-activi ty relationship. METHODS: Radioligand assay in vitro with a two-site m odel program analysis. RESULTS: Four THPB with two hydroxyl groups on C-2 and C-9 or C-2 and C-10 exhibited R-H and R-L two binding sites to D-1 receptors and guanosine triphosphate regulated the R-H binding si te of SPD and THPB-132A in competition assay, while eleven THPB includ ing nonhydroxy-THPB, monohydroxy-THPB, and THPB with two hydroxyl grou ps attaching to C-3 and C-10 showed one binding site to D-1 receptors under the same conditions. However, the tested eleven THPB all manifes ted one binding site to D-2 receptors in competition assay, and the 2- hydroxy-THPB had the most potent affinity for D-2 receptors. CONCLUSIO N: Dihydroxy-THPB with two hydroxyl groups attaching to C-2 and C-9 or C-2 and C-10 possess the intrinsic activity of agonist to D-1 recepto rs, while the other THPB do not. The tested eleven THPB all are the an tagonists of D-2 receptors.