TY - JOUR
T1 - Involvement of GABAergic pathway in the sedative activity of apigenin, the main flavonoid from Passiflora quadrangularis pericarp
AU - Gazola, Andressa C.
AU - Costa, Geison M.
AU - Castellanos, Leonardo
AU - Ramos, Freddy A.
AU - Reginatto, Flávio H.
AU - Lima, Thereza C.M. de
AU - Schenkel, Eloir P.
PY - 2015/3
Y1 - 2015/3
N2 - In the current study we showed that oral administration of an aqueous extract of Passiflora quadrangularis L., Passifloraceae, pericarp results in a significant prolongation of the sleep duration in mice evaluated in the ethyl ether-induced hypnosis test which indicates sedative effects. Apigenin, the main flavonoid of the extract, induced a similar sedative response when applied alone, at a dose equivalent to that found in the extract, suggesting that apigenin is mediating the sedative effects of P. quadrangularis extract. In addition, the sedative effect of apigenin was blocked by pretreatment with the benzodiazepine antagonist flumazenil (1 mg/kg), suggesting an interaction of apigenin with gamma-aminobutyric acid type A (GABAA) receptors. However, apigenin at concentrations 0.1–50 μM failed to enhance GABA-induced currents through GABAA receptors (α1β2γ2S) expressed in Xenopus oocytes. Nevertheless, based on our results, we suggest that the in vivo sedative effect of the P. quadrangularis extract and its main flavonoid apigenin maybe be due to an enhancement of the GABAergic system.
AB - In the current study we showed that oral administration of an aqueous extract of Passiflora quadrangularis L., Passifloraceae, pericarp results in a significant prolongation of the sleep duration in mice evaluated in the ethyl ether-induced hypnosis test which indicates sedative effects. Apigenin, the main flavonoid of the extract, induced a similar sedative response when applied alone, at a dose equivalent to that found in the extract, suggesting that apigenin is mediating the sedative effects of P. quadrangularis extract. In addition, the sedative effect of apigenin was blocked by pretreatment with the benzodiazepine antagonist flumazenil (1 mg/kg), suggesting an interaction of apigenin with gamma-aminobutyric acid type A (GABAA) receptors. However, apigenin at concentrations 0.1–50 μM failed to enhance GABA-induced currents through GABAA receptors (α1β2γ2S) expressed in Xenopus oocytes. Nevertheless, based on our results, we suggest that the in vivo sedative effect of the P. quadrangularis extract and its main flavonoid apigenin maybe be due to an enhancement of the GABAergic system.
UR - http://dx.doi.org/10.1016/j.bjp.2015.03.009
U2 - 10.1016/j.bjp.2015.03.009
DO - 10.1016/j.bjp.2015.03.009
M3 - Artículo
SN - 0102-695X
JO - Revista Brasileira de Farmacognosia
JF - Revista Brasileira de Farmacognosia
ER -