RESUMO
Objective To observe the effect of heat stress-induced burst out of reactive oxygen on neuronal apoptosis and investigate pathogenesis of brain damage caused by severe heat stroke.Methods Neurons heat stress model is set up.Control group were incubated at 37 ℃,5%CO2 ,While heat stress group of cells were incubated at 43 ℃for 2 h,then all the cells were further incubated at 37 ℃for different time as indicated.The amounts of ROS were assayed by DCFH staining at 0 h,0.5 h,1 h,2 h after heat stress.Apoptosis was analyzed by flow cytometry using Annexin V-FITC/PI staining and expression of caspase-3 were determined by westen blotat 0 h、3 h、6 h、12 h after heat stress.In addition,MnTMPyP is the specificscavengers of ROS,which effect on apoptosis is also studied at 12 h after heat stress.Results Compared with control group,amounts of ROS was significant increased at 0 h after heat stress,the burst out of it was at 2 h after heat stress (P<0.05 ).Apoptosis was induced at 3h after heat stress ,it was significant increased at 12 h after heat stress (43.2%,P<0.05 ).The expression of caspase-3 was also significant increased at 12 h after heat stress (P<0.05 ),and its trend was consistent with apoptosis rate trend.In addition,the scavengers MnTMPyP significantly decreased the apoptosis (47.42% to 18.45%, P<0.05 )and expression of caspase-3 at 12 h after heat stress.Conclusions An upstream signaling molecules,ROS could mediate heat stress-induced neuronal apoptosis,but its intermediate mechanism needs for further studies.