Welcome to 2 minute neuroscience, where I explain neuroscience topics in 2 minutes or less. In this installment I will discuss dopamine. Dopamine is a monoamine neurotransmitter, a term that refers to its chemical structure and the fact that it is derived from an amino acid.
Dopamine is also a catecholamine, a term that also refers to its chemical structure and the fact that it contains a catechol nucleus. To synthesize dopamine, the amino acid tyrosine is converted to L-dopa. Then L-DOPA is decarboxylated to form dopamine.
There are several areas of the brain where dopamine neurons are concentrated. The largest are the substantia nigra and ventral tegmental area in the midbrain. Other areas include the hypothalamus, olfactory bulb, and retina.
There are several major dopamine pathways that carry dopamine from these areas of concentration to other parts of the brain. Some of the largest are the mesostriatal or nigrostriatal pathway, which stretches from the substantia nigra to the striatum, the mesolimbic pathway, which stretches from the ventral tegmental area to the nucleus accumbens and other limbic structures, and the mesocortical pathway, which stretches from the ventral tegmental area throughout the cerebral cortex. Dopamine acts at G-protein coupled receptors and there are at least 5 subtypes of the dopamine receptor.
Dopamine is removed from the synaptic cleft by a transporter protein called the dopamine transporter. Like any neurotransmitter, the functions of dopamine are complex, and can’t be fully explained with just a short summary. Dopamine is linked to movement due to disorders like Parkinson’s disease that involve dopamine deficiencies.
It is also often associated with the processing of rewarding experiences. However, dopamine also plays a role in many other functions.
