ABSTRACT
Aim To explore the effects of Nrf2-ARE signal path on levrtiracetam anti-epileptic and levrtiracetam on learning and memorizing ability.Methods Thirty-six SD rats were divided into normal saline group, levrtiracetam group, model group and treatment group.Each group recruited nine rats.Tests of Morries water maze were given to the rats to evaluate their learning and memorizing ability.The protein expression of nuclear factor (erythroid-derived2)-like2 (Nrf2), heme oxygenase 1(HO-1) and NAD(P)H quinone oxidoreductase(NQO1) were examined by Western blot.Results Compared with model group, levrtiracetam could shorten the plateau period in epileptic rats (P<0.05), and increase the expression of Nrf2 protein, HO-1 protein and NQO1 protein in hippocampus(P<0.05).Conclusions Levrtiracetam could improve the learning and memorizing ability in epileptic rats.Levrtiracetam may increase the expression of HO-1 protein and NQO1 protein through the Nrf2-ARE pathway and play a part in antiepileptic effects.
ABSTRACT
Background Influence of weightlessness on visual function has been a hot topic in aerospace medicine field.Electroretinography (ERG) is valuable tool of evaluating visual function.Objective This study aims to observe the influence of head down tilt simulated weightlessness on ERG.MethodHead down tilt for 6° was adopted in 6 healthy volunteers.Flash ERG,including rod response,maxium response,cone response,oscillatory potentials (OPs) and 30 Hz flicker was recorded,and the latency and amplitude from each wave were analyzed before,two days and five days after trial.The record procedure followed the ISCEV standard for full field clinical electroretinography (2008 update).Oral informed consent was obtained from all the subjects prior to the trail.Results No significant differences were detected in the latencies and amplitudes of a,b waves of cone response and 30 Hz flicker among various time points(P＞0.05).The latencies were significantly prolonged in b wave of rod and a,b waves of maxim responses(P＜0.01),but no obvious change was found in amplitudes (P＞0.05).Both the latency and amplitude of all of the wavelets of OPs were considerably among the different time points(P＜0.05-0.01),and the ∑OPs was evidently different among the different time points(P＜0.05).Conclusion Head down tilt simulated weightlessness induce the abnormality of visual function in the early stage.
ABSTRACT
Objective To observe the influence of head-down tilt on visual evoked potential.Methods Six healthy volunteers were exposed to-6? head-down tilt.The visual evoked potential were measured before the test,the second day and the fifth day of the test under different space frequency.Results No significant difference was found in the latency of P100 before and after the test.The amplitude of P100 had significant change under high space frequency.But not the same happened on middle and low space frequency.Conclusion head-down tilt can induce the change of visual evoked potential under high space frequency,which means the weightlessness may influent the visual function.