Antidepressant-like effect of the hydroethanolic leaf extract of Alchornea cordifolia (Schumach. & Thonn.) Mull. Arg. (Euphorbiaceae) in mice: Involvement of monoaminergic system

作者：Ishola Ismail O; Agbaje Esther O^*; Akinleye Moshood O; Ibeh Chris O; Adeyemi Olufunmilayo O

来源：Journal of Ethnopharmacology, 2014, 158: 364-372.

DOI：10.1016/j.jep.2014.10.008

• Alchornea cordifolia
• alpha-adrenoceptor
• 5-HT1B receptor
• Depression
• Forced swimming test
• Parachlorophenylalanine

Ethnopharmacological relevance: The leaf of Alchornea cordifolia (Euphorbiaceae) is used in traditional African medicine in the treatment of various neurological and psychiatric disorders including depression. Previous studies have shown its potent antidepressant-like effect in the forced swimming test (FST). Hence, this study sought to investigate the involvement of monoaminergic systems in the antidepressant-like effect elicited by hydroethanolic leaf extract of Alchornea cordifolia (HeAC) in the FST.
Materials and methods: HeAC (25-400 mg/kg, p.o.) was administered 1 h before the FST. To investigate the contribution of monoaminergic systems to antidepressant-like effect, receptors antagonists were injected 15 min before oral administration of HeAC (200 mg/kg) to mice and 1 h thereafter, subjected to FST.
Results: HeAC (200 and 400 mg/kg, p.o.) produced dose dependent and significant (P<0.001) antidepressant-like effect, in.the FST, without accompanying changes in spontaneous locomotor activities in the open-field test. The anti-immobility effect of HeAC (200 mg/kg) in the FST was prevented by pretreatment of mice with SCH 23390 (0.05 mg/kg, s.c., a dopamine D-1 receptor antagonist), sulpiride (50 mg/kg, i.p., a dopamine D-2 receptor antagonist), prazosin (1 mg/kg, i.p., an alpha(1)-adrenoceptor antagonist), yohimbine (1 mg/kg, i.p., an alpha(2)-adrenoceptor antagonist), and GR 127993 (5-HT1B receptor antagonist). Similarly, 3 days intraperitoneal injection of p-chlorophenylalanine (pCPA, 150 mg/kg, i.p., an inhibitor of serotonin synthesis) prevented the antidepressant-like effect elicited by HeAC. The combination of subeffective doses of imipramine (5 mg/kg, p.o.) or fluoxetine (5 mg/kg, p.o.), with HeAC (25 mg/kg, p.o., subeffective dose) produced a synergistic antidepressant-like effect in the FST.
Conclusion: The hydroethanolic extract of Alchornea cordifolia possesses antidepressant-like effect mediated through interaction with dopamine (D-1 and D-2), noradrenergic (alpha(1) and alpha(2) adrenoceptors), and serotonergic (5HT(1B) receptors) systems. Also, the potentiation of the anti-immobility effect of conventional antidepressants (fluoxetine and imipramine) by Alchornea cordifolia suggest potential therapeutic effect in depression.

• 出版日期2014-12-2