The standardized extract of Loeselia mexicana possesses anxiolytic activity through the ¦Ã-amino butyric acid mechanism

详细信息    查看全文

• 作者：Maribel  ; Herrera-Ruiz^a ; Adolfo  ; Gonzá ; lez-Carranza^a ;   ; ^b ; Alejandro  ; Zamilpa^a ; Enrique  ; Jim&eacute ; nez-Ferrer^a ; Maira  ; Huerta-Reyes^a ; Ví ; ctor M.  ; Navarro-Garcí ; a^a ;   ; ^{vicmanchem@gmail.com}
• 关键词：Anxiety ; Elevated plus maze ; Coumarins ; Loeselia mexicana ; GABA_A receptor ; GABA antagonists
• 刊名：Journal of Ethnopharmacology
• 出版年：2011
• 出版时间：18 November 2011
• 年：2011
• 卷：138
• 期：2
• 页码：261-267
• 全文大小：518 K

文摘

Ethnopharmacological relevance

Loeselia mexicana (Lam.) Brand has been used in Mexican Traditional Medicine to treat ¡°espanto?or ¡°susto?(fear), which is a culturally affiliated syndrome whose symptomatology comprises loss of appetite, difficulty in sleeping, and also nausea and fatigue, with a sensation of fear or risk ?real or imagined ?to external stimuli.

Aim of the study

The anxiolytic effect of the standardized methanol extract of Loeselia mexicana, with regard to its content of coumarin daphnoretin, was researched utilizing the elevated plus maze (EPM) in order to demonstrate whether the biological effect produced by the plant is antagonized by drugs that block ¦Ã-amino butyric acid (GABA)ergic transmission.

Materials and methods

The methanolic extract of Loeselia mexicana (LmMeOH) was tested at different doses on the EPM and then the interaction of this extract was evaluated in the same model with different GABAergic drugs, such as flumazenil (FLU) 10 mg/kg, bicuculline (BIC) 5 mg/kg, pentylenetetrazole (PTZ) 10 mg/kg, and picrotoxin (PTX) 2 mg/kg. The effect of all of these treatments was evaluated by means of the open field test (OFT). Coumarin content was measured by the high performance liquid chromatography (HPLC) technique.

Results

The 200- and 400-mg/kg doses of methanolic extract containing 3.14 and 6.28 mg of daphnoretin, respectively, induced an anxiolytic effect in the EPM without modification of the spontaneous motor activity. The anxiolytic activity of 200 mg/kg of methanolic extract in EPM-exposed mice was antagonized by PTX, BIC, and FLU, but not by PTZ.

Conclusion

The data presented here indicate that the Loeselia mexicana Brand methanolic extract possesses a significant anxiolytic effect that appears to be mediated in part by activation of the GABAergic system.