Details

Autor(en) / Beteiligte

• Schoenfeld, Timothy J
• McCausland, Hayley C
• Morris, H. Douglas
• Padmanaban, Varun
• Cameron, Heather A

Titel

Stress and loss of adult neurogenesis differentially reduce hippocampal volume

Ist Teil von

• Biological psychiatry (1969), 2017-12, Vol.82 (12), p.914-923

Ort / Verlag

United States: Elsevier Inc

Erscheinungsjahr

2017

Quelle

MEDLINE

Beschreibungen/Notizen

• Abstract Background Hippocampal volume loss is a hallmark of clinical depression. Chronic stress produces volume loss in the hippocampus in humans and atrophy of CA3 pyramidal cells and suppression of adult neurogenesis in rodents. Methods To investigate the relationship between decreased adult neurogenesis and stress-induced changes on hippocampal structure and volume, we compared the effects of chronic unpredictable restraint stress and inhibition of neurogenesis in a rat pharmacogenetic model. Results Chronic unpredictable restraint stress over 4 weeks decreased total hippocampal volume, reflecting loss of volume in all hippocampal subfields and in both dorsal and ventral hippocampus. In contrast, complete inhibition of adult neurogenesis for 4 weeks led to volume reduction only in the dentate gyrus. With prolonged inhibition of neurogenesis, for 8 or 16 weeks, volume loss spread to the CA3 region, but not CA1. Combining stress and inhibition of adult neurogenesis did not have additive effects on the magnitude of volume loss but did produce a volume reduction throughout the hippocampus. One month of chronic unpredictable restraint stress and inhibition of adult neurogenesis both led to atrophy of pyramidal cell apical dendrites in dorsal CA3, and neuronal reorganization in ventral CA3. Stress significantly affected granule cell dendrites as well. Discussion The findings suggest that adult neurogenesis is required to maintain hippocampal volume but is not responsible for stress-induced volume loss.