| The brain is the key organ of stress load,and the impact of stress on the brain is good or bad.Correctly handling stress events is the foundation of human physical and mental health.Stress is the pathogenic factor of many mental diseases,and it has always been one of the research hotspots.Existing studies have shown that different stresses have different effects on the function of the same brain region,the same stress has different effects on the structure and function of different brain regions,and autophagy is involved in the regulation of stress on the structure and function of the brain.However,the effects of different stresses on autophagy kinetics in cerebral regions are not clear at present.Therefore,we will explore the effects of different stress on autophagy in the hippocampus,medial prefontal cortex(mPFC)and amygdala.Experimental purpose: To explore the changes of autophagy flow of cells in the hippocampus,mPFC and the basolateral amygdala under different stress patterns.Experimental method: 2-3 month male rats were divided into 12 groups: 1.control group(Control);2.15 minutes after restraint stress(RS-15 group);3.30-minute after restraint stress(RS-30 group);4.60 minutes after restraint stress(RS-60 group);5.15 minutes after foot-electrical stimulation(FS-15 group);6.30 minute after foot-electrical stimulation(FS-30 group);7.The 60 minutes after footelectrical stimulation(FS-60 group);8.DMSO group;9.15 minutes after intraperitoneal injection of 5mg/kg corticosterone(CORT5-15 group);10.30 minutes after intraperitoneal injection of 5mg/kg corticosterone(CORT5-30 group);11.60-minute after intraperitoneal injection of 5mg/kg corticosterone(CORT5-60group);12.Injection of 2mg/kg corticosterone per day(CORT 2-7 d group).After experiencing different stress conditions in each group,the SD rats were sacrificed and then the expressions of p-ULK1-s757,P62,LC3-II and LC3-I and other autophagy-related proteins in the hippocampus,the basolateral amygdala and the medial prefrontal cortex were detected by Western-Blot.Experimental results:1、In hippocampus: In RS-15 group,the expression of p-ULK1-s757 increased significantly;P62 increased significantly;LC3-I decreased significantly.In RS-30 group,the expression of p-ULK1-s757 decreased significantly.LC3-II/LC3-I increased significantly.The expression of p-ULK1-s757 in RS60 group increased significantly.P62 increased significantly.In FS-15 group,LC3-II/LC3-I decreased significantly.LC3-II decreased significantly;LC3-I decreased significantly.In FS-30 group,LC3-II/LC3-I decreased significantly.In FS-60 group,LC3-II decreased significantly.LC3-I decreased significantly.In CORT5-15 group p-ULK1-s757 and P62 increased significantly.In CORT5-60 group,P-ULK1-s757 increased significantly;P62 increased significantly.In CORT2-7d group,p-ULK1-s757,P62,LC3-II/LC3-I,LC3-II and LC3-I had no significant changes.2、In mPFC: in RS-15 group,the expression of LC3-I and LC3-II increased significantly,P62 decreased significantly,and other proteins had no difference.In RS-30 group,LC3-II/LC3-I increased significantly,and there was no difference in other proteins.In RS60 group,the expression of p-ULK1-s757 and P62 decreased significantly.The expression of other proteins was no difference.In FS-15 group,p-ULK1-s757 decreased significantly.P62 decreased significantly;LC3-II/LC3-I decreased significantly;LC3-II decreased significantly;LC3-I decreased significantly.In FS-30 group,LC3-II/LC3-I decreased significantly.In FS-60 group,P62 increased significantly;LC3-II increased significantly.In CORT5-15 group,LC3-II/LC3-I increased significantly.In CORT5-30 group,P62 decreased significantly.LC3-II and LC3-I decreased significantly.In CORT5-60 group,p-ULK1-s757 decreased significantly;P62 decreased significantly;LC3-II/LC3-I increased significantly;LC3-II increased significantly.In CORT2-7d group,P62 decreased significantly.3、In BLA: in RS-15 group,the expression of p-ULK1-s757 increased significantly,LC3-I decreased significantly,and LC3-II decreased significantly.The expressions of p-ULK1-s757,LC3-II/LC3-I,LC3-I,LC3-II and P62 in RS-30 group,FS-30 group,FS-60 group and CORT5-30 group were not significantly different.In RS60 group,the expression of p-ULK1-s757 increased significantly.The expression of P62 increased significantly(p <0.05),but LC3-I and LC3-II were decreased significantly.In FS-15 group,P62 decreased significantly;p-ULK1-s757,LC3-II,LC3-I,LC3-II/LC3-I have no significant difference.In CORT5-15 group,LC3-II/LC3-I increased significantly and LC3-II increased significantly;p-ULK1-s757,P62 and LC3-I have no significant influence.In CORT5-60 group,LC3-II/LC3-I increased significantly;LC3-I increased significantly;LC3-II increased significantly.In CORT2-7d group,LC3-II/LC3-I increased significantly.Conclusion:1.Different stress patterns have different effects on autophagy of cells in the same brain region,especially mPFC and BLA.2.The influence of the same stress on autophagy in brain regions will change with time.3.Long-term administration of corticosterone enhanced autophagy in mPFC and BLA brain regions.4.The difference of autophagy in brain region after stress suggests that the change of autophagy may be the change of brain structure and function and the cellular biochemical mechanism of related mental diseases. |
