Figure 4. How nerve cells communicate with neurotransmitters.

Different cells in the brain contain distinct neurotransmitters that attach to different receptors.  You have probably heard the names of many of the neurotransmitters in the brain. They include norepinephrine, dopamine, serotonin, GABA (g aminobutyric acid), and many others (NINDS, 2007).

Methamphetamine is a chemical and it works in the brain by changing the way neurotransmitters are released from cells and/or attach to their receptors, or even by acting like neurotransmitters.  Some drugs can activate neurons because their chemical structures are very similar to the brain’s neurotransmitters. When these drugs attach to receptors, it can result in abnormal messages being sent between nerve cells. Other drugs, such as methamphetamine or cocaine, can cause the nerve cells to release abnormally large amounts of natural neurotransmitters or prevent the normal recycling of these brain chemicals.  This disruption produces a greatly amplified message, ultimately disrupting normal communication (NIDA, 2007).  Meth also interacts with specific neurotransmitter receptors and amplifies their actions.

What Neurotransmitters Are Involved in
Methamphetamine Abuse and Dependence?

Abuse of, and dependence of methamphetamine produces changes in many of the brains neurotransmitters and their receptors. Two of the most important are dopamine and GABA.

Dopamine
Most of the pleasurable effects of methamphetamine in the brain are thought to result from the release of very high levels of the neurotransmitter dopamine. Dopamine is involved in motivation, the experience of pleasure, and motor function; and is a common mechanism of action for most drugs of abuse. The parts of the brain thought to be most greatly affected by dopamine are shown in Figure 5 (NIDA, 2006).