One of the ways to regulate dopamine (DA) neurotransmission is the reuptake process, which involves the influx of DA from the extracellular space into the cytosol. In addition to the highly selective dopamine transporter (DAT), there are low-affinity monoamine transporters (organic cation transporters, OCT) that regulate extracellular DA levels when its concentration significantly exceeds normal levels. Rats lacking DAT (DAT-KO) exhibit chronic hyperdopaminergia, motor hyperactivity and stereotypies. Quinine is an inhibitor of extrasynaptic dopamine (DA) uptake and blocks OCT. In this study, quinine was used to investigate DA regulation under normal conditions and in the context of hyperdopaminergia