·AIM:To establish a new method to record visual evoked potential of rats and this method was applied to retinal cone degeneration (RCD) and congenital stationary night blindness (CSNB) rats to see whether it is feasible.·METHODS:After anesthesia,the rats scalp surface was exposed and two stainless screws were implanted at 4mm in front of and 8mm behind Bregma.The front one was reference electrode and the latter one was recording electrode.The ground electrode was joined to the tail.And we recorded VEP of scotopic adaptation and photopic adaptation (The stimulus intensity of light :0.011,0.035,0.11,0.35,1.1 and 3.5cd·s/m2.They were all overlapped for 100 times.There were 2-5minutes intervals between different intensities.The frequency of stimulation was 1Hz and time course was 300 milliseconds).A week later,we recorded the VEP again in the same conditions.·RESULTS:The rats who were implanted with electrodes could live longer.When they were recorded,there was no disturbance and the waveforms were very clear and steady.There was no difference between the waveforms recorded by conventional method and those by implanted electrodes while the amplitude of new method was larger than conventional.We could get the same conclusion in RCD and CSNB rats.·CONCLUSION:Since the electrodes can be kept on the scalp for a longer time,we can not only observe dynamic changes of VEP but also observe the long-duration patho-logical changes in the rats.Because the positions of recording and reference electrodes were fixed,the system error can be reduced and the repeatability of experiments increased.·
Qun Guo,Bei Xie,Yong-Hao Gu,Jing An,Feng Xia,Zuo-Ming Zhang Department of Clinical Aerospace Medicine,Faculty of Aerospace Medicine,the Fourth Military Medical University,Xi’an 710032,Shaanxi Province,China
