Journal of Rafsanjan University of Medical Sciences

Background and Objectives: Role of different parts of the brain in stress management, especially nucleus accumbens (NAc), is not well known. In this study the role of NAc in response to chronic stress in male mice were evaluated.

Materials and Methods: In this experimental study, intra-accumbal uni- and bi-lateral cannulation was performed by stereotaxic instrument. Five minutes before stress induction, 2% lidocaine solution was administered to the animals intra-accumbally. Stress by Communication Box induced to the animals between 9-11 am for 4 consecutive days (8 groups of 6). Plasma corticosterone, food and water intake, animals’ weight gain, and delay time in food intake were measured as stress metabolic signs. Data were analyzed using two-way analysis of variance.

Results: Stress increased plasma corticosterone and delayed the eating time (p<0.001) and had no significant impact on weight changes and water intake. Lidocaine administration could not completely inhibit the plasma corticosterone levels and delays to eating time, compared with the control group. NAc transient inactivation inhibited stress in animals’ food intake (p<0.001) and weight (p<0.05), significantly. As well as, lidocaine administration either unilateral of right or left side or bilateral decreased water intake (p<0.05).

Conclusion: It seems that NAc, as a brain structure, plays a role in mediation of chronic stress effects on metabolic functions. There are also some differences between the right and left sides of the NAc which may reflect a kind of side bias in the functions of the NAc.

Key words: Chronic stress, Lidocaine, Nucleus accumbens

Funding: This research was funded by  Neuroscience Research Center, Baqiyatallah (AS) University of Medical Sciences.

Conflict of interest: None declared.

Ethical approval: The Ethics Committee of Baqiyatallah (AS) University of Medical Sciences approved the study.

How to cite this article: Eftekhari F, Sahraei H, Alibeik H, Rezaeian J, Nikaeili F, Ghamari F, Sarahian N. Role of Nucleus Accumbens in Response to Chronic Stress in Small Male NMRI Mouse. J Rafsanjan Univ Med Sci 2016; 15(4): 319-30. [Farsi]