Stress induced cognitive deficit is differentially modulated in BALB/c and C57Bl/6 mice: Correlation with Th1/Th2 balance after stress exposure

Received 27 July 2009; received in revised form 25 October 2009; accepted 9 November 2009. published online 30 November 2009.

Abstract

This work shows a comparative study on the effects of chronic mild stress upon learning and memory and immunity, in BALB/c and C57BL/6 mice. Stressed BALB/c, but not C57Bl/6 mice, showed a poor learning performance, morphological alterations in the hippocampus with an increase in oxidative stress. A correlation between poor memory performance and the increase of the Th2/Th1 balance was found. Our results suggest that vulnerability to cognitive deficit associated with stress exposition could be related to a differential regulation of Th1/Th2 cytokine balance, suggesting a better learning performance for individuals that produce Th1 type cytokine after stress exposition.

Keywords: Chronic mild stress, Hippocampus, Learning and memory, Th1/Th2 balance, Reactive oxygen species, BALB/c and C57BL/6 inbred strains of mice

a CEFYBO-CONICET, 1a. Cátedra de Farmacología, Facultad de Medicina, UBA, Argentina

b Instituto de Biología Celular y Neurociencias Prof. De Robertis, Facultad de Medicina, UBA, Argentina

Corresponding author. CEFYBO-CONICET, 1a. Cát. de Farmacología, Facultad de Medicina, UBA, Paraguay 2155, Piso 15, 1121 Ciudad de Buenos Aires, Argentina. Tel.: +54 11 4962 4431x116; fax: +54 11 4962 4431x106.

PII: S0165-5728(09)00464-0

doi:10.1016/j.jneuroim.2009.11.005

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