Early life stress paradigms in rodents: potential animal models of depression?

• Published in: Psychopharmacology Vol. 214; no. 1; pp. 131 - 140
• Main Authors: Schmidt, Mathias V., Wang, Xiao-Dong, Meijer, Onno C.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.03.2011; Springer; Springer Nature B.V
• Subjects: Analysis; Animals; Behavior, Animal; Biomedical and Life Sciences; Biomedicine; Children & youth; Depression - etiology; Depression - physiopathology; Depression, Mental; Disease Models, Animal; Humans; Life Change Events; Mental depression; Mice; Neurosciences; Neurosecretory Systems - metabolism; Pharmacology/Toxicology; Psychiatry; Rats; Review; Risk Factors; Rodents; Stress; Stress (Psychology); Stress, Psychological - complications; Animal model; Depression; Early life stress; Stress
• ISSN: 0033-3158; 1432-2072; 1432-2072
• DOI: 10.1007/s00213-010-2096-0

Rationale While human depressive illness is indeed uniquely human, many of its symptoms may be modeled in rodents. Based on human etiology, the assumption has been made that depression-like behavior in rats and mice can be modulated by some of the powerful early life programming effects that are known to occur after manipulations in the first weeks of life. Objective Here we review the evidence that is available in literature for early life manipulation as risk factors for the development of depression-like symptoms such as anhedonia, passive coping strategies, and neuroendocrine changes. Early life paradigms that were evaluated include early handling, separation, and deprivation protocols, as well as enriched and impoverished environments. We have also included a small number of stress-related pharmacological models. Results We find that for most early life paradigms per se, the actual validity for depression is limited. A number of models have not been tested with respect to classical depression-like behaviors, while in many cases, the outcome of such experiments is variable and depends on strain and additional factors. Conclusion Because programming effects confer vulnerability rather than disease, a number of paradigms hold promise for usefulness in depression research, in combination with the proper genetic background and adult life challenges.