The first nerve releases a neurotransmitter into the gap between the cells. The neurotransmitter either stimulates or inhibits the second nerve. To avoid overstimulation, the first nerve will then reabsorb the neurotransmitter. Cocaine acts on the brain s reward pathway, the pathway that makes us feel good when we eat, drink, have sex, or engage in other activities that contribute to our survival as individuals and as a species. Stimulating this pathway provides a vital sense of satisfaction.
Cocaine acts on nerves in the pathway that produce the neurotransmitter dopamine.
When a nerve releases dopamine, cocaine blocks reuptake. The body has natural balancing processes, and eventually the second nerve will become less sensitive to this increased concentration of dopamine. Further, since the first nerve cannot reabsorb the dopamine it releases, it eventually runs out of dopamine. Cocaine elsewhere in the body Cocaine has a similar effect outside the brain, on nerves that use the neurotransmitter noradrenaline. Cocaine blocks re-uptake of noradrenaline, and thus affects the activity of the heart, blood vessels and genitalia, causing heart irregularities, increased blood pressure, and sometimes sexual stimulation.