Dopamine is one of a number of chemicals known as a neurotransmitters that carry signals from various cells in the brain. Dopamine acts on several neurons and has been implicated in addiction and movement disorders. Learning where dopamine-producing cells are located, how dopamine is produced and what dopamine does will greatly enhance your understanding of the brain's chemical messenger system.
Messenger
Brain cells, called neurons, use chemicals like dopamine to send information to each other. Dopamine is stored by certain nerve cells and released upon stimulation. The dopamine is then sensed by cells with receptors designed to recognize the shape and structure of dopamine. This triggers a reaction in the receiving cell. Depending on the receiving cell, dopamine can be involved in movement control, sensations of reward and pleasure or emotions.
Addiction
According to the University of Texas, drugs of abuse, such as cocaine, often alter dopamine function. These drugs can increase the concentration of dopamine in your brain by either stimulating dopamine release or preventing its reuptake. This leads to stimulation of dopamine receptors causing feelings of pleasure and happiness. Addicts seek to recapture this feeling by taking more drugs.
Location
Neurons producing dopamine are clustered in the substantia nigra. This is a crescent-shaped cell mass in the middle brain that appears darkly pigmented. According to Medline Plus, these nerve cells send fibers to cells located on both sides of the brain.
Drug Interactions
Drugs of abuse are not the only drugs that affect dopamine concentrations. Drugs that inhibit dopamine reuptake include methylphenidate, which the University of Texas says is used to treat childhood hyperkinesis and symptoms of schizophrenia. The drug Levodopa is a synthetic form of dopamine used in combination with Carbidopa to treat Parkinson's disease. Drugs are also available to decrease the amount of dopamine available in the brain. These drugs often act to promote dopamine breakdown.
Movement
Dopamine is involved in movement coordination and initiation. When the dopamine-producing cells in the substantia nigra die or become impaired, Parkinson's disease results. According to MayoClinic.com Patients with Parkinson's disease exhibit resting tremors, slowed movement, rigid muscles, and impaired posture and balance. The disease is treated by attempting to replace missing Dopamine with synthetic dopamine.
