Downregulation of BDNF mRNA in the hippocampal dentate gyrus after re-exposure to cues previously associated with footshock.
This study examined the effects of footshock stress and re-exposure to cues previously associated with footshock on expression of brain-derived neurotrophic factor (BDNF) mRNA in the hippocampus of male rats. Exposure to twenty 0.5-s 0.4-mA footshocks co-terminating with 70 dB, 5-s long pure tones over 60 min decreased dentate gyrus BDNF mRNA by 21.5%. Baseline BDNF mRNA levels returned to normal by two days after footshock exposure. Re-exposure for 60 min to the chamber and tones previously paired with 0.4 mA footshock decreased BDNF mRNA by 12%. Re-exposure to the conditioning chamber and tones previously paired with 0.6 mA footshock over 60 min decreased BDNF mRNA by 20.8%. The data suggest that psychological, as well as unconditioned physical stress, can decrease hippocampal BDNF mRNA. Possible implications for stress-related and other neuropsychiatric disorders associated with deficits in hippocampal function and volume, such as depression, post-traumatic stress disorder, and Alzheimer's Disease, are discussed.
Rasmusson
Ann M
AM
VA National Center for PTSD, Clinical Neuroscience Division, West Haven, CT, USA. ann.rasmusson@yale.edu
Shi
Libin
L
Duman
Ronald
R
D000161:Acoustic Stimulation; D000818:Animals; D001362:Avoidance Learning / Q000502:physiology; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics*; D003213:Conditioning, Psychological / Q000502:physiology*; D003463:Cues; D018891:Dentate Gyrus / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D003863:Depression / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D015536:Down-Regulation / Q000502:physiology*; D004558:Electric Stimulation / Q000009:adverse effects; D005239:Fear / Q000502:physiology; D008297:Male; D009473:Neuronal Plasticity / Q000502:physiology; D009474:Neurons / Q000378:metabolism / Q000473:pathology; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013313:Stress Disorders, Post-Traumatic / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D013315:Stress, Psychological / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology
D019208:Brain-Derived Neurotrophic Factor; D012333:RNA, Messenger