Document Type

Honors Project


Existing models of pain in zebrafish (Danio rerio) require injection of acetic acid into localized areas including the lips. We are currently developing an alternative assay of pain in zebrafish that involves immersion in dilute concentrations of acetic acid. This assay involves placing subjects in a 120 mL beaker containing 100 mL of water taken from the subject’s original tank. After a 20-minute acclimation period, the experimental substances are added, if applicable. Subjects are exposed to the experimental substances for 30 minutes (unless otherwise specified), after which they are returned to their original tanks. A series of studies was conducted to determine the optimal concentration of acetic acid to be used in this model, to determine any changes in behavioral response over two hours of exposure, and to investigate the effect of concomitant exposure to morphine sulfate (MS) on top-dwelling behavior. A significant increase in top-dwelling behavior was observed upon exposure to 0.03% acetic acid. This response remained relatively constant over the two-hour time course analysis. These results demonstrate a significant, replicable increase in top-dwelling behavior upon exposure to 0.03% acetic acid. The three concentrations of MS tested herein did not significantly affect top-dwelling behavior in the presence of acetic acid, so the underlying state motivating this behavior is unclear. These results could suggest that a pain state is not motivating the top-dwelling behavior. Alternatively, it is possible that the doses of MS used in the current study are sub-threshold. After further investigation, this paradigm could serve as a model for use in future pain research.

Included in

Psychology Commons



© Copyright is owned by author of this document