The Novel Tank Test: Handling Stress and the Context Specific Psychopharmacology of Anxiety

Background. The zebrafish has become a popular animal model for behavioral pharmacology. One of the greatest advantages of the zebrafish is its amenability for high throughput screens to identify anxiety altering compounds. The novel tank diving test is arguably one of the most commonly utilized behavioral tests for quantifying anxiety-like behavioral responses in zebrafish. However, a number of context-dependent anxiety-like behavioral responses have recently been reported in the literature for this task, and the validity of using a single measure, the diving response, has been questioned. Objective. In this review, we discuss multiple behavioral parameters that can be used to evaluate performance in the novel tank diving test which can serve as indicators of anxiety. In addition, we also discuss the difficulties associated with interpretation of behavioral measures of anxiety, a question complicated by context- dependent behavioral responses induced by handling the fish with a net, a known stressor. Conclusion. The zebrafish is a relative newcomer in the psychopharmacological analysis of anxiety, but the increasing number of efficient behavioural tests and the translational relevance of this species make the zebrafish a potentially useful laboratory species for screening of anxiolytic compounds.