Effects of morphine on conditioned place preference and pain are independent of uptake‑2.

Morphine changes neurotransmitter release, including norepinephrine, dopamine, and serotonin. Decynium‑22 (D22) inhibits an alternative neurotransmitter removal pathway, namely uptake‑2. Uptake‑2 includes plasma membrane monoamine transporter (PMAT) and organic cation transporters that have a low affinity, but high capacity for uptake of various monoamines such as norepinephrine, dopamine, and serotonin.

Involvement of the transient receptor potential A1 in morphine-induced conditioned place preference and physical dependence in mice.

The main side effects of opioid use are physiological and psychological dependence. The transient receptor potential channels, including transient receptor potential ankyrin 1 (TRPA1), are involved in various neurological disorders. We aimed to evaluate the effect of TRPA1 inhibition on morphine-induced conditioned place preference (CPP) and physical dependence.