Decynium-22 affects behavior in the zebrafish light/dark test

Abstract

Decynium-22 (D-22) is an inhibitor of the uptake2 system of monoamine clearance, resulting in increased levels of dopamine, norepinephrine, and serotonin in the nervous system and elsewhere. Uptake2 is mediated by low-affinity, high-capacity transporters that are inhibited by glucocorticoids, suggesting a mechanism of fast glugocorticoid-monoamine interaction in the brain. D-22 dose-dependently increased anxiety-like behavior in adult zebrafish exposed to the light/dark test, monotonically increasing scototaxis (dark preference), but affecting risk assessment with an inverted-U-shaped response. These results suggest that the uptake2 system has a role in defensive behavior in zebrafish, presenting a novel mechanism by which stress and glucocorticoids could produce fast neurobehavioral adjustments in vertebrates. Data: https://github.com/lanec-unifesspa/decynium22