Figure 4. Effect of two weeks chronic morphine treatment (1.5 mg/L), 24-h morphine withdrawal and morphine withdrawal in presence of 2 mg/L mitragynine on the mRNA expression of CRF-R1, CRF-R2 and PDYN in zebrafish.

Data are presented as mean ± SEM of three independent experiments. Mean values were subjected to one way ANOVA and where applicable, ranked by Tukey test (P<0.05); mean percentage values with same letter are not significantly different.