HTR1A and Anxiety: In the light/dark test, exposure to an aversive olfactory stimulus (alarm substance) greatly increases anxiety-like behavior, an effect which is blocked by acute fluoxetine treatment but not by the 5-HT1A antagonist WAY 100,635 (Maximino et al., 2014c); WAY 100,635 was able to block the fear-induced analgesia caused by alarm substance (Maximino et al., 2014c), and low doses of this drug blocked the effect of alarm substance on behavior in the novel tank test (Nathan et al., 2015).