Clomipramine Effects on Anxiety-Like Behaviors in Zebrafish: A Research Note

Abstract

Studies suggest that diagnoses of depressive and/or anxiety disorders have drastically increased, leading to increased use of antidepressants. More research is needed to understand whether and how antidepressants modulate anxiety. Proxy studies based on animal subjects help inform such inquiries. The current analysis tests the efficacy of the drug clomipramine, a tricyclic antidepressant, on anxietylike behaviors in an animal model. The 55 adult (about 6-months old), mixed-sex, wild-type zebrafish were either part of the control group or given doses of 0.125, 0.25, 0.50, or 1.00 mL/L of clomipramine for 20 minutes. The novel tank test was applied to determine whether the drug had either anxiolytic (reduced anxiety-like behavior) or anxiogenic (increased anxiety-like behavior) effects based on the following six behavioral measures; distance traveled, mean speed, resting time, total time in the top, total distance in the top, and entries to the top. Findings show mixed dose-response outcomes. Mean speed decreased with dosage, while both time in the top and entries to the top increased with dosage. Yet the three remaining tests had inconsistent results. These findings represent preliminary animal-model observations requiring replication.