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Suppressed proliferation and apoptotic changes in the rat dentate gyrus after acute and chronic stress are reversible
Author(s) -
Heine Vivi M.,
Maslam Suharti,
Zareno Jessica,
Joëls Marian,
Lucassen Paul J.
Publication year - 2004
Publication title -
european journal of neuroscience
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.346
H-Index - 206
eISSN - 1460-9568
pISSN - 0953-816X
DOI - 10.1046/j.1460-9568.2003.03100.x
Subject(s) - dentate gyrus , chronic stress , apoptosis , hippocampal formation , hippocampus , cell growth , bromodeoxyuridine , neurogenesis , endocrinology , medicine , cell , biology , neuroscience , biochemistry
Acute stress suppresses new cell birth in the hippocampus in several species. Relatively little is known, however, on how chronic stress affects the turnover, i.e. proliferation and apoptosis, of the rat dentate gyrus (DG) cells, and whether the stress effects are lasting. We investigated how 3 weeks of chronic unpredictable stress would influence the structural dynamic plasticity of the rat DG, and studied newborn cell proliferation, survival, apoptosis, volume and cell number in 10‐week‐old animals. To study lasting effects, another group of animals was allowed to recover for 3 weeks. Based on two independent parameters, bromodeoxyuridine (BrdU) and Ki‐67 immunocytochemistry, our results show that both chronic and acute stress decrease new cell proliferation rate. The reduced proliferation after acute stress normalized within 24 h. Interestingly, chronically stressed animals showed recovery after 3 weeks, albeit with still fewer proliferating cells than controls. Apoptosis, by contrast, increased after acute but decreased after chronic stress. These results demonstrate that, although chronic stress suppresses proliferation and apoptosis, 3 weeks of recovery again normalized most of these alterations. This may have important implications for our understanding of the reversibility of stress‐related hippocampal volume changes, such as occur, for example, in depression.