Effects of serotonergic terminal lesion in the amygdala on conditioned fear and innate fear in rats.

The amygdala and the medial prefrontal cortex (mPFC) are crucial brain structures for anxiety, and it is speculated that the serotonergic neural system in these structures has an important role in regulating anxiety. In our previous study, we indicated that local injections of selective serotonin reuptake inhibitor into the amygdala attenuated anxiety-related behaviors in conditioned fear in rats. In the present study, we investigated the effects of serotonergic terminal lesions in the amygdala and in mPFC induced by local injection of 5,7-dihydroxytryptamine (5,7-DHT), on anxiety-related behaviors in conditioned fear and the elevated plus-maze test in rats.

Corticotropin releasing factor enhances attentional function as assessed by the five-choice serial reaction time task in rats.

Previous studies have shown that psychological stress affects attentional function, and corticotropin releasing factor (CRF) is closely related to stress responses. In the present study, we examined the effect of CRF on attentional function using a five-choice serial reaction time task (5-CSRTT) in rats. Accuracy in the 5-CSRTT was used as the index of attentional function.