behavioral sensitization in danio rerio

behavioral sensitization in danio rerio

Abstract

Background

Accumulating evidence sugges that aviorbehal sensitization is involved in the process of drug addiction. Zebrafish are sensitive to a variety of addictive drugs and are thus suitable for the study of behavioral sensitization. However, in contrast to mature rodent models of behavioral sensitization, how this phenomenon manifests in aquatic organisms, especially zebrafish, is largely unknown. In this study, we developed a morphine-induced behavioral sensitization adult zebrafish model and performed a preliminary investigation of the underlying mechanisms.

Methods

Behavioral sensitization was established in zebrafish by observing their behavior after treatment and challenge with morphine. The effect of morphine was evaluated by a behavioral locomotor test. Different doses of morphine and withdrawal times were used to evaluate the establishment of the behavioral sensitization model.

Results

Hyperlocomotion was induced after administration of morphine in adult zebrafish. After withdrawing the drug for a period, challenge with low-dose morphine evoked behavioral sensitization in zebrafish acutely pre-treated with morphine. Low-dose morphine failed to induce behavioral sensitization in zebrafish if the withdrawal time was less than 5 days or more than 7 days. Morphine induced behavioral sensitization in zebrafish may involve dopaminergic, glutamatergic and opioid systems.

Conclusion

A single low-dose of morphine could induce behavioral sensitization in zebrafish acutely pre-treated with morphine, and this phenomenon was highly correlated with drug dose and withdrawal time. These findings suggest that zebrafish is a suitable model for the study of behavioral sensitization.

Keywords

Zebrafish
Behavioral sensitization
Morphine
Drug addiction

Abbreviations

CPP
conditioned place preference
GABA
γ-aminobutyric acid
D1R
dopamine 1 receptor
D2R
dopamine 2 receptor
AMPA
α-amino-3-hydroxy-5-methyl-4-isoxazolepropioniac acid
mGluR
metabotropic glutamate receptors
CNS
central nervous system