Abstract
Methods: Males Wistar rats (290-320 grs) were restrained during 1 hour or 30 minutes and immediately or 30 minutes after stress sacrificed for immunochemistry assay. Another group of animals, were cannulated in the lateral septum or the basolateral amygdala for the infusion of olomucine (40 nm/ul) a Cdk5 inhibitor; or isolomucine (40 nm/ul) an inactive analogous of olomucine; or vehicule 15 min before restraint. One day later, anxiety was measured in the elevated plus maze (EPM).
Results: A 1 h stress session increased the levels of Cdk5 and p35 in cingulate cortex (Cg), cortical amygdala (ACo) and dorsal lateral septum (LSD) whereas 30 minutes of restraint increased the levels of p35 in basal amygdala (BLA), dentate gyrus (DG) and the dorsomedial portion of periaqueductal grey substance (PAGDM). Also, restraint reduced the percentage of time spent in open arms of EPM and this decrease was normalized by olomucine, but not after isolomucine or vehicule, administered either in the lateral septum or in the basolateral amygdala.
Conclusions: Stress increases the expression of Cdk5 y p35 in brain areas involved in the processing of emotional information. This enhancement, at least in lateral septum and basolateral amygdala, could be functionally associated with the generation of emotional sensitization.
