title: Propofol prevents electroconvulsive-shock-induced memory impairment through regulation of hippocampal synaptic plasticity in a rat model of depression.
abstract: BACKGROUND
  Although a rapid and efficient psychiatric treatment, electroconvulsive therapy (ECT) induces memory impairment. Modified ECT requires anesthesia for safety purposes. Although traditionally found to exert amnesic effects in general anesthesia, which is an inherent part of modified ECT, some anesthetics have been found to protect against ECT-induced cognitive impairment. However, the mechanisms remain unclear. We investigated the effects of propofol (2,6-diisopropylphenol) on memory in depressed rats undergoing electroconvulsive shock (ECS), the analog of ECT in animals, under anesthesia as well as its mechanisms.
  
  
  METHODS
  Chronic unpredictable mild stresses were adopted to reproduce depression in a rodent model. Rats underwent ECS (or sham ECS) with anesthesia with propofol or normal saline. Behavior was assessed in sucrose preference, open field and Morris water maze tests. Hippocampal long-term potentiation (LTP) was measured using electrophysiological techniques. PSD-95, CREB, and p-CREB protein expression was assayed with Western blotting.
  
  
  RESULTS
  Depression induced memory damage, and downregulated LTP, PSD-95, CREB, and p-CREB; these effects were exacerbated in depressed rats by ECS; propofol did not reverse the depression-induced changes, but when administered in modified ECS, propofol improved memory and reversed the downregulation of LTP and the proteins.
  
  
  CONCLUSIONS
  These findings suggest that propofol prevents ECS-induced memory impairment, and modified ECS under anesthesia with propofol improves memory in depressed rats, possibly by reversing the excessive changes in hippocampal synaptic plasticity. These observations provide a novel insight into potential targets for optimizing the clinical use of ECT for psychiatric disorders.
authors.affiliation: Department of Anesthesiology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, People's Republic of China.
authors.forename: Jie
authors.initials: J
authors.lastname: Luo
authors.affiliation: Department of Anesthesiology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, People's Republic of China.
authors.forename: Su
authors.initials: S
authors.lastname: Min
authors.affiliation: Department of Anesthesiology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, People's Republic of China.
authors.forename: Ke
authors.initials: K
authors.lastname: Wei
authors.affiliation: Department of Anesthesiology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, People's Republic of China.
authors.forename: Jun
authors.initials: J
authors.lastname: Cao
authors.affiliation: Department of Anesthesiology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, People's Republic of China.
authors.forename: Bin
authors.initials: B
authors.lastname: Wang
authors.affiliation: Department of Anesthesiology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, People's Republic of China.
authors.forename: Ping
authors.initials: P
authors.lastname: Li
authors.affiliation: Department of Anesthesiology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, People's Republic of China.
authors.forename: Jun
authors.initials: J
authors.lastname: Dong
authors.affiliation: Department of Anesthesiology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, People's Republic of China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Liu
keywords: CREB; PSD-95; electroconvulsive therapy; long-term potentiation