Effect of estrogen on motion sickness susceptibility in rats

Abstract

Objective:To investigate the effect of estrogen on motion sickness susceptibility in rats.Methods:Thirty rats were randomly divided into 5groups.Motion sickness models were established by rotation stimulation.Sixty minutes before exposure to rotation stimulation,rats in the 4groups were subcutanously injected with normal saline 0.5ml/kg,6mg/ml estradiol 0.5ml/kg,4mg/ml estrogenαreceptor agonist(0.5ml/kg)and 4mg/ml estrogenβreceptor agonist(0.5ml/kg),respectively.And rats in another group was gavaged with 4mg/ml tamoxifen(5ml/kg).The intake of kaolin and the motion sickness scores were used as perimeters to evaluate the seriousness of motion sickness,and the expression of estrogen receptor mRNA in hypothalamus following rotation stimulation was determined by RT-PCR.Results:When compared with the normal saline group,the intake of kaolin and the motion sickness scores for the estradiol group and estrogenαreceptor agonist group elevated considerably and symptoms of motion sickness were severer,while symptoms of motion sickness for the rats in the tamoxifen group were obviously lighter.The expression of estrogenαreceptor mRNA in hypothalamus increased significantly following rotation stimulation.Conclusion:Administration of exogenous estrogen would aggravate motion sickness susceptibility,and estrogenαreceptor might play an important role in the induction of motion sickness.