Involvement of 5-HT1A Receptors in the Anxiolytic-Like Effects of Quercitrin and Evidence of the Involvement of the Monoaminergic System.

Qian-tong Liu,Yong Liu,Jin-li Shi,Jian-you Guo,Jian Li,Yi Chen,Jie Liu

doi:10.1155/2016/6530364

Abstract

Quercitrin is a well-known flavonoid that is contained in Flos Albiziae, which has been used for the treatment of anxiety. The present study investigated the anxiolytic-like effects of quercitrin in experimental models of anxiety. Compared with the control group, repeated treatment with quercitrin (5.0 and 10.0 mg/kg/day, p.o.) for seven days significantly increased the percentage of entries into and time spent on the open arms of the elevated plus maze. In the light/dark box test, quercitrin exerted an anxiolytic-like effect at 5 and 10 mg/kg. In the marble-burying test, quercitrin (5.0 and 10.0 mg/kg) also exerted an anxiolytic-like effect. Furthermore, quercitrin did not affect spontaneous locomotor activity. The anxiolytic-like effects of quercitrin in the elevated plus maze and light/dark box test were blocked by the serotonin-1A (5-hydroxytryptamine-1A (5-HT1A)) receptor antagonist WAY-100635 (3.0 mg/kg, i.p.) but not by the γ-aminobutyric acid-A (GABAA) receptor antagonist flumazenil (0.5 mg/kg, i.p.). The levels of brain monoamines (5-HT and dopamine) and their metabolites (5-hydroxy-3-indoleacetic acid, 3,4-dihydroxyphenylacetic acid, and homovanillic acid) were decreased after quercitrin treatment. These data suggest that the anxiolytic-like effects of quercitrin might be mediated by 5-HT1A receptors but not by benzodiazepine site of GABAA receptors. The results of the neurochemical studies suggest that these effects are mediated by modulation of the levels of monoamine neurotransmitters.

Highlights

Anxiety is a state of excessive fear and characterized by psychomotor tension, sympathetic hyperactivity, and vigilance [1]
We explored the anxiolytic-like effects of quercitrin using the elevated plus maze (EPM), light/dark box (LDB) test, and marble-burying test
The oneway analysis of variance (ANOVA) revealed significant differences between groups in the time spent on the open arms (F7,127 = 4.330, p < 0.01, Figure 2(a)), percentage of open arm entries (F7,127 = 3.123, p < 0.05, Figure 2(b)), percentage of the time spent in the closed arms (F7,127 = 4.140, p < 0.01, Figure 2(c)), percentage of closed arm entries (F7,127 = 3.342, p < 0.01, Figure 2(d)), and percentage of the time spent in the central areas (F7,127 = 1.692, p > 0.05, Figure 2(e))

Summary

Introduction

Anxiety is a state of excessive fear and characterized by psychomotor tension, sympathetic hyperactivity, and vigilance [1]. Benzodiazepines are the most common drugs that have been used for the treatment of anxiety, but these compounds have obvious side effects, such as sedation, muscle relaxation, amnesia, and dependence potential [3,4,5]. Flos Albiziae is the dry flowers or flower buds of Albizia julibrissin Durazz., which have been used for the treatment of insomnia, amnesia, sore throat, and contusion in traditional oriental medicine [7]. Our previous study showed that the total flavones contained in Albizia julibrissin exerted anxiolytic effects [8]. Quercitrin is the major component of flavonoids contained in Flos Albiziae [9]. The anxiolytic potential of quercitrin has not yet been reported

Methods

Results

Discussion

Conclusion