, Volume 46, Issue 5, pp 417–423 | Cite as

Long-Term Administration of Cod Liver Oil Ameliorates Cognitive Impairment Induced by Chronic Stress in Rats

  • Emil TrofimiukEmail author
  • Jan J. Braszko
Original Article


Cod liver oil (CLO) is a rich source of omega-3 fatty acids (FA), especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The existing data suggest that EPA and DHA are the active agents of fish oil. In this study, we tested a hypothesis that the active constituents of CLO alleviate the negative impact of prolonged restraint stress on cognitive functions of male Wistar rats. Specifically, we attempted to characterize the preventive action of long-lasting treatment with CLO [0.375 ml/100 g body weight (equivalent to a dose of 300 mg/kg DHA and 225 mg/kg EPA), p.o. for 21 days] against an impairment caused by chronic restraint stress (2 h daily for 21 days) on recall as tested in a passive avoidance situation and on the spatial reference and working memory tested in a Barnes maze as well as on locomotor activity and anxiety behavior tested respectively in an open field and elevated plus-maze. We found that CLO administration statistically significantly (p < 0.01, both) prevented the deleterious effects of chronic restraint stress on recall and the spatial memory.


Cod liver oil Stress Open field Elevated plus maze Passive avoidance Barnes maze Spatial memory 



Alzheimer’s disease


One-way analysis of variance


Brain-derived neurotrophic factor


Barnes maze


Cod liver oil


Ca(2+)/calmodulin-dependent protein kinase II


Docosahexaenoic acid


Eicosapentaenoic acid


Omega-3 fatty acids


Long-term potentiation


Medial prefrontal cortex


Morris water maze




Passive avoidance


Polyunsaturated fatty acids


Standard error of mean



This study was supported by the Medical University of Bialystok (3-66775L).


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Copyright information

© AOCS 2011

Authors and Affiliations

  1. 1.Department of Clinical PharmacologyMedical University of BialystokBialystokPoland

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