Pharmacological studies of geissoschizine methyl ether, isolated from Uncaria sinensis Oliv., in the central nervous system

Citation
T. Pengsuparp et al., Pharmacological studies of geissoschizine methyl ether, isolated from Uncaria sinensis Oliv., in the central nervous system, EUR J PHARM, 425(3), 2001, pp. 211-218
Citations number
36
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Pharmacology & Toxicology
Journal title
EUROPEAN JOURNAL OF PHARMACOLOGY
ISSN journal
0014-2999 → ACNP
Volume
425
Issue
3
Year of publication
2001
Pages
211 - 218
Database
ISI
SICI code
0014-2999(20010817)425:3<211:PSOGME>2.0.ZU;2-Y
Abstract
The pharmacological properties of geissoschizine methyl ether, isolated fro m Uncaria sinensis Oliv., were analyzed in vitro and in vivo using mice cen tral serotonin neurons. In the in vitro experiment, geissoschizine methyl e ther inhibited [H-3]8-hydroxy-2-(di-n-propylamino)tetralin) ([H-3]8-OH-DPAT ) (K-i = 0.8 muM), [H-3]mesulergine (K-i = 0.9 muM) and [H-3]ketanserin (K- i = 1.4 muM), but had less affinity toward [H-3]prazosin (K-i > 10 muM) and [H-3]spiperone (K-i > 15 muM) binding to mouse brain membranes. The in viv o studies showed that geissoschizine methyl ether dose-dependently reduced 5-hydroxy-L-tryptophan (I-5-HTP) plus clorgyline-induced head twitch respon se without inhibiting the I-5-HTP plus clorgyline and 8-OH-DPAT-induced hea d weaving. On the other hand, geissoschizine methyl ether also decreased th e rectal temperature of mice (hypothermic response) in a dose-dependent man ner. These results suggest that geissoschizine methyl ether possesses mixed 5-HT1A receptor agonist/5-HT2A/2C receptor antagonist activities and inhib its the head twitch response by blocking the 5-HT2A receptors, and possibly , at least in part, by stimulating the 5-HT1A receptors in the central nerv ous system. (C) 2001 Elsevier Science B.V. All rights reserved.