Transient inactivation of the nucleus accumbens reduces both the expression and acquisition of morphine-induced conditioned place preference in rats

► Morphine can induce dopamine-related behaviors. ► Inhibition of left and right side of nucleus accumbens shell can inhibit morphine preference. ► Dopamine-related behaviors also were altered when left side was inhibited. ► Inhibition of left and right side of nucleus accumbens core also inhibit morphine preference. ► Dopamine-related behaviors were altered when right side was inhibited.