Anti-anxiety effects of Apocynum venetum L. in the elevated plus maze test.
The purpose of this study was to characterize the putative anxiolytic-like activity of an ethanolic extract prepared from the leaves of Apocynum venetum (AV) using the elevated plus maze (EPM) in mice. Male C75BL/6 mice were either treated orally with the AV extract or the positive controls diazepam and buspirone, respectively, 1h before behavioral evaluation in the EPM. A single treatment of AV extract markedly increased the percentage time spent on and the number of entries into the open arms of the EPM in doses of 30 and 125 mg/kg p.o., respectively. This effect was comparable to that of the benzodiazepine diazepam (1.5 mg/kg p.o.) and the 5-HT(1A) agonist buspirone (10 mg/kg p.o.). The effects of AV in 125 mg/kg were effectively antagonized by the benzodiazepine antagonist flumazenil (3 mg/kg i.p.). However, the effects of AV extract could only partially be blocked by the unspecific 5-HT(1A) receptor antagonist WAY-100635 (0.5 mg/kg i.p.). Neither diazepam and buspirone nor the AV extract produced any overt behavioral change or motor dysfunction in the open field test. These results indicate that AV extract is an effective anxiolytic agent, and suggest that the anxiolytic-like activities of this plant are mainly mediated via the GABAergic system.
Grundmann
Oliver
O
College of Pharmacy, Department of Pharmaceutics, University of Florida, Gainesvilla, FL 32610, USA.
Nakajima
Jun-Ichiro
J
Seo
Shujiro
S
Butterweck
Veronika
V
D000818:Animals; D014151:Anti-Anxiety Agents / Q000737:chemistry / Q000494:pharmacology*; D001007:Anxiety / Q000188:drug therapy; D030010:Apocynum / Q000737:chemistry*; D001522:Behavior, Animal / Q000187:drug effects; D002065:Buspirone / Q000494:pharmacology; D003975:Diazepam / Q000494:pharmacology; D004195:Disease Models, Animal; D000431:Ethanol; D005442:Flumazenil / Q000494:pharmacology; D018757:GABA Modulators / Q000494:pharmacology*; D008297:Male; D018782:Maze Learning / Q000187:drug effects*; D051379:Mice; D008810:Mice, Inbred C57BL; D010879:Piperazines / Q000494:pharmacology; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D010946:Plants, Medicinal / Q000737:chemistry; D011725:Pyridines / Q000494:pharmacology; D018079:Receptors, GABA / Q000187:drug effects; D012702:Serotonin Antagonists / Q000494:pharmacology
D014151:Anti-Anxiety Agents; D018757:GABA Modulators; D010879:Piperazines; D010936:Plant Extracts; D011725:Pyridines; D018079:Receptors, GABA; D012702:Serotonin Antagonists; D000431:Ethanol; D005442:Flumazenil; C090413:N-(2-(4-(2-methoxyphenyl)-1-piperazinyl)ethyl)-N-(2-pyridinyl)cyclohexanecarboxamide; D003975:Diazepam; D002065:Buspirone