Electroconvulsive stimulations normalizes stress-induced changes in the glucocorticoid receptor and behaviour.
Animal models of chronic stress, such as 21 days of 6h/daily restraint stress cause changes in neuronal morphology in the hippocampus and alter behaviour. These changes are partly mediated by the glucocorticoids. The objective of this study was threefold: (1) to study how this particular chronic stress paradigm influences expression of hippocampal glucocorticoid receptor mRNA, (2) to study the effect of previous repeated restraint stress on the behaviours executed in the forced swim test (FST) (e.g. a novel inescapable stress situation) and (3) to investigate the modulating effect of electroconvulsive stimulations (ECS) on the neural and behavioural effects of the stress paradigm. The study shows that restraint stress lowered glucocorticoid receptor mRNA levels in all hippocampal regions, including the CA3 region which is the site of the characteristic dendritic reorganization seen in this model. Furthermore, stressed rats displayed higher increases in immobility and decreased latency to immobility subjected to the novel stressor of the FST than non-stressed rats. ECS abolished both the neural and behavioural effects of the restraint stress and thus protected against the deleterious effects of the stress paradigm. The clinical relevance of these findings is discussed.
Hageman
Ida
I
Laboratory of Neuropsychiatry, Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, 2100 Copenhagen, Denmark. ida.hageman@rh.regionh.dk
Nielsen
Marianne
M
Wortwein
Gitta
G
Diemer
Nils Henrik
NH
Jorgensen
Martin Balslev
MB
D000311:Adrenal Glands / Q000502:physiology; D000704:Analysis of Variance; D000818:Animals; D001835:Body Weight / Q000502:physiology; D004558:Electric Stimulation; D015870:Gene Expression; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism*; D017403:In Situ Hybridization; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D017966:Pyramidal Cells / Q000166:cytology / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D011965:Receptors, Glucocorticoid / Q000235:genetics*; D018161:Receptors, Mineralocorticoid / Q000235:genetics; D012149:Restraint, Physical / Q000009:adverse effects / Q000379:methods; D013315:Stress, Psychological / Q000209:etiology / Q000503:physiopathology*; D013550:Swimming; D013997:Time Factors
D012333:RNA, Messenger; D011965:Receptors, Glucocorticoid; D018161:Receptors, Mineralocorticoid