Format

Send to

Choose Destination
Behav Brain Res. 2017 Mar 30;322(Pt A):138-144. doi: 10.1016/j.bbr.2017.01.008. Epub 2017 Jan 3.

Mice subjected to uncontrollable electric shocks show depression-like behaviors irrespective of their state of helplessness.

Author information

1
Department of Anatomy, College of Medicine, Korea University, Seoul, Republic of Korea. Electronic address: jinyea@korea.ac.kr.
2
Department of Anatomy, College of Medicine, Korea University, Seoul, Republic of Korea. Electronic address: soohyun86@korea.ac.kr.
3
Division of International Studies, Korea University, Seoul, Republic of Korea. Electronic address: jennakwon95@gmail.com.
4
Department of Anatomy, College of Medicine, Korea University, Seoul, Republic of Korea. Electronic address: biocais@korea.ac.kr.
5
Department of Anatomy, College of Medicine, Korea University, Seoul, Republic of Korea. Electronic address: kimhyun@korea.ac.kr.

Abstract

The unpredictable and inescapable electric shock-induced "learned helplessness" paradigm has long been used to produce an animal model of depression to identify the molecules associated with depressive symptoms or to assess the efficacy of pharmacological treatments for depression. After exposure to unpredictable and inescapable shocks (uncontrollable stress), most of mice showed defect in escape behavior in active avoidance test (learned helplessness, LH), while others did not (non-learned helplessness, NLH). Here, we investigated whether mice with LH or NLH exhibited depressive symptoms, including anhedonia, anxiety, and despair. We found that compared with control naïve mice, both uncontrollable shocks-induced LH and NLH mice showed increased anhedonia- and anxiety- but not despair-like behaviors. Notably, mice subjected to uncontrollable shocks showed similar behaviors, irrespective of whether they also showed LH or NLH. Furthermore, since both LH and NLH mice showed only anhedonia- and anxiety- but not despair-like behaviors, this model may be generally inadequate for classic depression-like behavior assessment. In conclusion, uncontrollable electric shock induces depression-like behavior, irrespective of the state of helplessness.

KEYWORDS:

Active avoidance; Depression; Depression animal model; Electric foot shock; Learned helplessness

PMID:
28062258
DOI:
10.1016/j.bbr.2017.01.008
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center