PMC

Flow diagram showing the CPP procedure and time required for each step.

CPP apparatus. (a,b) Image showing the CPP tank (a) and a graphical representation of the tank (b) with the position of the dividers and dimensions indicated, adapted from a previously published paper.

Conditioned place preference behavior in adult zebrafish.
(a) Place preference behavior of naive adult zebrafish treated with morphine sulfate (MS) at different concentrations. MS was dissolved in system water and appropriate volumes of this stock solution were added to the tank water before conditioning. Mean percent preferences ± s.e.m. values are shown. <p> C = control (n = 25), MS 1.5 μM (n = 9), MS 3 μM (n = 23), MS 7.5 μM (n = 13) and MS 15 μM (n = 13). Dunett’s T3 test, **P < 0.005.
(b) Change in preference for the conditioned compartment of control (n = 8) and drug-treated animals treated with 0.5% (n = 11), 1% (n = 11) and 1.5% (n = 8) (vol/vol) ethanol. Change in preference = (percent time in the ethanol-paired compartment after conditioning) − (percent time in the same compartment before conditioning). Error bars are means ± s.e.m. Student’s t-test, P = 0.0409 (*) for 1.5% (vol/vol) ethanol compared with 0% ethanol. Panel a is adapted from a previously published paper.