CONICET | Buscador de Institutos y Recursos Humanos

The hippocampus is a brain-structure related with learning and memory. Hippocampus is sensitive to the stress effects. In previous reports, we found that chronic mild stress (CMS) model induced cognitive deficit in mice. This was correlated with a decrease in adult neurogenesis and Th1/Th2 balance in lymphocytes. We also observed a decrease in neural nitric oxide synthase (nNOS) activity and protein levels and an increase in endothelial nitric oxide synthase (eNOS) in hippocampus of CMS mice. Moreover, other authors related the genes G protein subunit alpha q (GNAQ), cAMP responsive element binding protein (CREB) and glycogen synthase kinase 3 beta (GSK-3b) with plasticity neuronal process such as neurogenesis, neuronal differentiation, dendritic growth and in several psychiatric disorders. All these genes are expressed in lymphocytes. The aim of the present work was correlate the eNOS, nNOS, GNAQ, CREB and GSK-3b genes expression in hippocampus, lymph nodes and spleen with cognitive deficit in female BALB/c mice exposed to CMS model. The spontaneous alternation percentage was evaluated by Y-maze. We found a poor performance in the Y-maze in CMS mice respect to control mice (p  0.01). The mRNA levels of the all genes were analyzed by qRT-PCR. The mRNA level of eNOS (p0.05), nNOS (p0.05) and GNAQ (p0.05) decrease in hippocampus and nNOS (p0.05) level decease in lymph nodes of stressed mice respect to control. The GNAQ (p0.05), GSK-3b (p0.01) and CREB (p 0.01) expression decrease in spleen of CMS mice. The other genes did not show significant differences in the studied tissues. These findings indicate the nNOS and GNAQ genes could be potential peripheral markers of cognitive deficit. More studies are necessary to demonstrated this hypothesis.