Rats selected as "anxious", "nonanxious," or normal according to their beha
vior in an elevated plus maze were submitted to memory tasks and the densit
ies of central benzodiazepine receptors in the amygdala and the hippocampus
were studied. Anxious rats exibited better retention scores in the inhibit
ory avoidance task while nonanxious rats exibited worse retention scores in
inhibitory and two-way active avoidance tasks compared to normal rats. No
significant differences were detected in the retention scores for habituati
on to an open field. Nonanxious rats presented a lower benzadiazepine recep
tor density in the hippocampus but not in the amygdala compared to the othe
r groups. These data suggest that the benzodiazepine receptors are involved
in the effect of "anxiety" or emotional states on memory storage processes
. (C) 1999 Academic Press.