What neurotransmitters are believed to be blocked by cocaine, affecting its behavior?

Cocaine primarily affects the brain's reward system by blocking the reuptake of certain neurotransmitters, particularly dopamine. When dopamine is released in the brain, it is normally taken back up into the neurons that released it. Cocaine inhibits this reuptake process, leading to increased levels of dopamine in the synaptic cleft, which dramatically enhances its signaling effect. This elevation of dopamine is associated with feelings of euphoria and increased energy, which are characteristic of cocaine use.

Serotonin is also involved in mood regulation, and while cocaine does influence serotonin pathways to some extent, its primary and most profound impact is on dopamine. The enhancement of serotonin due to cocaine's action is not the main factor in its behavioral effects; instead, it is the heightened dopamine activity that largely drives the euphoric and addictive properties of the drug.

Other choices include neurotransmitters like norepinephrine, acetylcholine, GABA, and endorphins, which may play roles in various behavioral and physiological functions, but cocaine's most significant action relevant to its behavioral effects centers around the blockade of dopamine reuptake. This mechanism contributes to both the stimulating effects of cocaine and its potential for addiction.