Brazilein, a Selective 5-HT Receptors Antagonist in Mouse Uterus

AimTo prove brazilein's effect on 5-HT receptor and to understand the characteristics of the action.MethodsIn this work, the blocking effect of brazilein on 5-HT receptor subtypes was investigated in isolated uterine strips using pharmacological (selective agonists) and molecular biological (real time PCR) approaches.Resultsbrazilein does not affect the contractions of normal mice uterus, but inhibits uterine excitatory elicited by ergometrine maleate (pA2 = 5.71 ± 0.21), a 5-HT2 receptor agonist. The excitatory effects of 5-HT1D, 5-HT2A and 5-HT2C receptor agonists on uterus could be inhibited by brazilein (pA2 = 4.58 ± 0.06, 4.91 ± 0.15, 5.38 ± 0.15, respectively). The mRNA expression of 5-HT1D and 5-HT2C receptors in mice uterus were decreased by brazilein.Conclusionbrazilein blocked 5-HT receptors in mice uterus and might affect the functions mediated by 5-HT receptors.