Open AccessPropranolol can induce PTSD ‐like memory impairments in rats
Author(s) -
Zhu RongTing,
Liu XiangHui,
Shi YanWei,
Wang XiaoGuang,
Xue Li,
Zhao Hu
Publication year - 2018
Publication title -
brain and behavior
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.915
H-Index - 41
ISSN - 2162-3279
DOI - 10.1002/brb3.905
Subject(s) - propranolol , memory consolidation , fear conditioning , neuroscience , hippocampus , freezing behavior , psychology , antagonist , medicine , receptor , amygdala
One hallmark symptom of post‐traumatic stress disorder ( PTSD ) is an inability to restrict fear responses to the appropriate predictor. An infusion of glucocorticoids ( GC s) after a high‐intensity shock has been shown to induce PTSD ‐like memory impairments. In addition to GC s, noradrenergic signalling is also recognized as a key biomarker underlying PTSD symptomatology. Methods To explore the role of the noradrenergic system in PTSD ‐like memory impairments, in this study, various doses of the β‐adrenoceptor antagonist propranolol were systemically or bilaterally injected into the dorsal hippocampus immediately after unpaired cue‐shock contextual fear conditioning, and then the rats were tested 24 h later. Results Interestingly, we found that only low‐dose propranolol could induce PTSD ‐like memory impairments, as rats showed reduced freezing to the correct predictor and generalized fear responses to the safe cues, accompanied by increased NE levels in the hippocampus and altered neural activity within the frontal‐subcortical circuit. Conclusion These findings demonstrate that the noradrenergic system is involved in regulating the consolidation of contextual fear memory and that propranolol can dose‐dependently induce PTSD ‐like memory impairments.