MKP-1在PTSD样大鼠海马组织中表达改变

Study of MKP-1 expression alteration in the hippocampal tissue of the PTSD rats

目的探讨创伤后应激障碍(PTSD)样大鼠行为学改变与海马组织中丝裂原活化蛋白激酶磷酸酶-1(MKP-1)表达的关系。方法将30只清洁级SD大鼠随机分为Control组、PTSD 1 d组、PTSD 3 d组、PTSD 7 d组、PTSD 14 d组,每组各6只,使用国际认定的单次延长应激(SPS)方法制作大鼠PTSD模型。通过旷场试验、Morris水迷宫观察大鼠的行为学变化。采用实时荧光定量PCR(qRT-PCR)和Western blot法分别检测大鼠海马组织中MKP-1 mRNA和蛋白水平的变化。结果 PTSD 7 d组、PTSD 14 d组与Control组相比直立次数、进格次数以及穿台次数减少,潜伏期延长,差异有统计学意义(P <0. 05)。PTSD 7 d组、PTSD 14 d组与Control组相比,海马组织中MKP-1 mRNA及蛋白表达水平明显升高,差异均具有统计学意义(P <0. 05)。结论 PTSD样大鼠行为改变、记忆下降考虑与海马组织中MKP-1基因及蛋白表达增高有关,MKP-1可能参与了PTSD的发病机制,有望作为PTSD发生发展的参考指标。

Objective To investigate the relationship between the behavioral changes of rats with posttraumatic stress disorder(PTSD)and the expression of mitogen-activated protein kinase phosphatase-1(MKP-1)in hippocampus.Methods Thirty SD rats of clean grade were randomly assigned into control group,PTSD 1 d group,PTSD 3 d group,PTSD 7 d group and PTSD 14 d group with 6 in each group.The PTSD rat model was made by an internationally recognized single prolonged stress(SPS)method.Open-field test and Morris water maze were used to observe the behavior changes in rats.Meanwhile,real time quantitative PCR(qRT-PCR)and Western blot were used to detect the changes of MKP-1 mRNA level and protein level in hippocampus of rats,respectively.Results Compared with the control group,the number of erect times,entry times and frequency of crossing the platform decreased and the incubation period of the rats was prolonged in PTSD 7 d and PTSD 14 d group(P<0.05).The expression level of MKP-1 mRNA and protein in the hippocampus of PTSD 7 d group and PTSD 14 d group were significantly higher than that in the control group(P<0.05).Conclusion Behavioral change and memory decline in rats with PTSD are considered related to the increased expression of MKP-1 gene and protein in hippocampus.MKP-1 probably be involved in the pathogenesis of PTSD,so the MKP-1 may serve as a reference index for the occurrence and development of PTSD.