Assessment of anti-depressant activity of omega 3 fatty acids in rodents


  • Arshaduddin Ahmed Syed Department of Pharmacology, Osmania Medical College, Kothi, Hyderabad, India
  • Kamathi Vipin Chandra Department of Global Pharmacovigilance, Aurobindo Pharma Ltd, Hyderabad, India



α-linolenic acid, Eicosapentaenoic acid, Forced swim test


Background: Depression contributes to significant disease burden at national and global levels. At the personal and domestic level too, depression leads to poor quality of life, causing a huge socioeconomic impact. In the world, over 300 million people are estimated to have depression and the numbers of depressed persons are only projected to go up.

Methods: The forced swim test (FST) is one of the most commonly used animal models for assessment of antidepressant effects in rodents. In the modified version of this test, the rats are forced to swim in a glass tank with no means of escape, inducing a behaviour of immobility, which resembles a state of despair, akin to depression in humans. The rats were divided into 6 groups: 1. control group: treated with distilled water; 2. standard group treated with fluoxetine Hcl (10mg/kg); 3.test-1 group treated with omega-3 FAs (300mg/kg); 4.test-2 group treated with a higher dose of omega-3 FAs (500 mg/kg); 5.test-3 group treated with omega-3 FAs (300mg/kg) and fluoxetine (10mg/kg); and 6.test-4 group treated with omega-3 FAs (500 mg/kg) and fluoxetine (10mg/kg).

Results: The independent between-groups ANOVA yielded a statistically highly significant result, F (5, 30) = 9.47, P <0.001. Thus, the null hypothesis of no difference between the means was rejected. To further evaluate the nature of the differences between the means of the six groups, the statically significant ANOVA result was followed by Tukey's honest significant difference post-hoc tests.

Conclusions: This study finds that omega 3 fatty acids have intrinsic antidepressant activity, and the combination of fluoxetine and omega 3 fatty acids has significantly more antidepressant effect than fluoxetine alone in the forced swim test done on Wistar rats.


World Health Organization, Geneva. Depression and other common mental disorders: global health estimates, 2017. Available at: Accessed 25 October 2017.

Amin G, Shah S, Vankar GK. The prevelance and recognition of depression in primary care. Indian J Psychiatry. 1998;40(4):364-9.

Nambi SK, Prasad J, Singh D, Abraham V, Kuruvilla A, Jacob KS. Explanatory models and common mental disorders among patients with unexplained somatic symptoms attending a primary care facility in Tamil Nadu. National Med J India. 2002 Jan 1;15(6):331-5.

Porsolt RD, Le Pichon M, Jalfre ML. Depression: a new animal model sensitive to antidepressant treatments. Nature. 1977 Apr;266(5604):730-2.

Detke MJ, Lucki I. Detection of serotonergic and noradrenergic antidepressants in the rat forced swimming test: the effects of water depth. Behavioural Brain Res. 1995 Dec 15;73(1-2):43-6.

Slattery DA, Cryan JF. Using the rat forced swim test to assess antidepressant-like activity in rodents. Nature Protocols. 2012 Jun;7(6):1009.

Castagné V, Moser P, Roux S, Porsolt RD. Rodent models of depression: forced swim and tail suspension behavioral despair tests in rats and mice. Current Protocols Pharmacol. 2010 Jun;49(1):5-8.

Castagné V, Porsolt RD, Moser P. Use of latency to immobility improves detection of antidepressant-like activity in the behavioral despair test in the mouse. Eur J Pharmacol. 2009 Aug 15;616(1-3):128-33.

Carlezon Jr WA, Mague SD, Parow AM, Stoll AL, Cohen BM, Renshaw PF. Antidepressant-like effects of uridine and omega-3 fatty acids are potentiated by combined treatment in rats. Biol Psychiatry. 2005 Feb 15;57(4):343-50.

Venna VR, Deplanque D, Allet C, Belarbi K, Hamdane M, Bordet R. PUFA induce antidepressant-like effects in parallel to structural and molecular changes in the hippocampus. Psychoneuroendocrinol. 2009 Feb 1;34(2):199-211.

Naliwaiko K, Araújo RL, Da Fonseca RV, Castilho JC, Andreatini R, Bellissimo MI, et al. Effects of fish oil on the central nervous system: a new potential antidepressant?. Nutritional neuroscience. 2004 Apr 1;7(2):91-9.

Stillwell W, Wassall SR. Docosahexaenoic acid: membrane properties of a unique fatty acid. Chem Physics Lipids. 2003 Nov 1;126(1):1-27.

Krishnan V, Nestler EJ. Linking molecules to mood: new insight into the biology of depression. Am J Psychiatry. 2010 Nov;167(11):1305-20.

James MJ, Gibson RA, Cleland LG. Dietary polyunsaturated fatty acids and inflammatory mediator production. Am J Clin Nutr. 2000 Jan 1;71(1):343s-8s.

Frick LR, Rapanelli M, Cremaschi GA, Genaro AM. Fluoxetine directly counteracts the adverse effects of chronic stress on T cell immunity by compensatory and specific mechanisms. Brain Behavior Immunity. 2009 Jan 1;23(1):36-40.

Martinowich K, Manji H, Lu B. New insights into BDNF function in depression and anxiety. Nature Neurosci. 2007 Sep;10(9):1089-93.

Nestler EJ, Barrot M, DiLeone RJ, Eisch AJ, Gold SJ, Monteggia LM. Neurobiology of depression. Neuron. 2002 Mar 28;34(1):13-25.

Alme MN, Wibrand K, Dagestad G, Bramham CR. Chronic fluoxetine treatment induces brain region-specific upregulation of genes associated with BDNF-induced long-term potentiation. Neural Plasticity. 2007;2007.




How to Cite

Syed, A. A., & Chandra, K. V. (2018). Assessment of anti-depressant activity of omega 3 fatty acids in rodents. International Journal of Basic & Clinical Pharmacology, 7(12), 2353–2358.



Original Research Articles