Recently we have reported that stress increase the expression of p35 selectively in the Basolateral Amygdala (BLA). This increase is consistent with an enhanced anxiety-like behaviour in stressed animals. In the present work, we try to elucidate if the normalization of this anxiogenic behavior with prior midazolam (MDZ) administration also prevents the increase on p35 expression induced by restraint. Adults Wistar rats (290-320 grs) received a dose of 0.5 mg/kg of MDZ i.p. or vehicle (VEH) and later on subjected to a 30 min restraint session. One day later, animals were behaviourally tested on the elevated plus maze (EPM). Another group of animals received a dose of 0.5 mg/kg of MDZ i.p. or vehicle (VEH) followed by the stressful experience. Thirty minutes after stress rats were sacrificed for the immunohistochemistry. Restraint provoked a significant and selective increase of p35 levels in BLA and an enhancement of the anxiety-like behavior. Both effects were prevented by prior MDZ administration.
