Roles of the 5-HT1A receptor in zebrafish responses to potential threat and in sociality
Anxiety is a normal emotion representing a reaction to potential danger, whereas fear can be defined as a reaction to real, explicit danger. Anxiety-like behavior in animal models has been associated with differences in the serotonergic system. Treatment of zebrafish cohorts with 8-OH-DPAT, a full agonist at the 5-HT1A receptor, decreased anxiety-like behavior in the novel tank test, but increased it in the light-dark preference test, both considered assays for anxiety-like behavior for this species. The same treatment decreased social approach in both the social investigation and social novelty phases of the social preference test. These effects suggest a participation of the 5-HT1A heteroreceptors in zebrafish anxiety and social preference, decreasing both. Thus, the study of this receptor is important for a better understanding of anxiety-like behavior in zebrafish and its relationship with similar phenomena in vertebrates.