A neurotransmitter is a chemical messenger that works for our nervous system and allows information to pass between neurons, or neurons and muscle cells or glands. There are numerous types of neurotransmitters, each with a determined function that enables the body to function correctly.
Among the main neurotransmitters, we find dopamine, a messenger that has traditionally been associated with love and pleasure but one that also has various other jobs in our bodies.
We will present a detailed analysis of dopamine, its functions and what role it plays in related medical conditions such as Parkinson's disease and addictions. We will also review the types of food associated with increased levels of dopamine and how supplements work to complement these.
Dopamine is an organic chemical (a neurotransmitter) of the catecholamine and phenethylamine families that plays several essential roles in the brain and body such as movement, pleasure, motivation, memory, or attention, among many others.
By neurotransmitter we mean a chemical substance released by neurons, or nerve cells, to send signals to other neurons. Our brain contains various neurological paths that facilitate the transmission of dopaminergic signals, each with its unique function and characteristic.
Aside from the dopaminergic paths, this neurotransmitter also functions outside of the nervous system, primarily as a local messenger. The effects of dopamine on the rest of the body range from dilation of the blood vessels (due to inhibiting norepinephrine), increasing the amount of sodium in the kidney, stimulating urine production, or decreasing insulin production.
Modified levels of dopamine have been connected to various diseases of the nervous system. Parkinson's disease is caused by an imbalance in an area of your brain called the substantia nigra. Cells that make the chemical dopamine start to die which affects the area of your brain that controls moving your body. Another medical condition associated with dopamine is schizophrenia, which is closely related to a reduced level of this hormone.
Finally, although prescription medicine that can influence the effect of dopamine currently exists on the market, there are also pharmacological intravenous substances that promise to have similar results. Although dopamine administered through an IV cannot reach the brain through the bloodstream, it has proven effective in treating heart failure due to its peripheral effects.
As mentioned prior, dopamine is a neurotransmitter released into the nervous system which governs various functions in the body. Some of the dopamine's primary roles have been connected to:
Pleasure and reward system
Behavior and cognition
Inhibiting the hormone prolactin
Dopamine is the main chemical in our brain that regulates how we perceive and experience pleasure. During pleasurable moments or situations, this neurotransmitter is released, which causes a person to seek out a desirable activity over and over again. Dopamine is released primarily in the prefrontal cortex and accumbens nucleus.
Examples of stimulant activities that release dopamine are eating, taking illicit drugs and having sexual intercourse.
Touching on the previous point, some drugs such as cocaine and amphetamines act as dopamine reuptake inhibitors, which means that using them allows dopamine to travel freely through our brain creating an increased sense of wellbeing.
By increasing the dopamine levels in the brain, pleasurable sensations are also elevated which means there is a higher risk of addiction seeing how the person using the drugs might want to repeat the experience.
The basal ganglia are a cerebral structure responsible for controlling and regulating the movement of our body and its proper functioning, which largely depends on the amount of dopamine that it receives.
In the case of a dopamine deficiency in the brain, the movements of the body can become uncoordinated, delayed or slowed, while an excess of this neurotransmitter may produce tics.
Dopamine traveling through the frontal lobes of the brain is responsible for controlling the flow of information to other areas of the brain.
Any imbalances in the level of this neurotransmitter in this area can cause cognitive issues connected to memory, attention, and problems solving.
According to various studies, dopamine also has a vital role in regulating our mood. Abnormal levels of this neurotransmitter, either too much or not enough, can trigger emotional imbalances such as anxiety, sadness, and depression.
Dopamine is the primary neuroendocrine inhibitor of prolactin secretion (a protein that enables mammals, usually females, to produce milk. ) The neurotransmitter acts on cells in the pituitary gland where prolactin is produced which is why it is also called prolactin-inhibiting hormone (PIH).
At the beginning of the article, we mentioned how dopamine is closely connected to the onset and development of various neurological conditions such as Parkinson's disease, ADHD, schizophrenia, bipolar disorder, and addictions.
Generally speaking, the disorders associated with altered levels of dopamine or their function are:
Aging of the brain
Dopamine can be found naturally in many types of food; the issue is that it cannot directly penetrate the blood flow and reach the brain. This means that a dopamine-rich diet alone will not be able to elevate the level of this neurotransmitter.
There is, however, a precursor to dopamine: tyrosine. This molecule can break through the blood-brain barrier which means that food containing it can alter the levels of the dopamine found in our brain.
Tyrosine is an amino acid that is naturally occurring in protein-rich food such as red meat, nuts, or cheese.
It has yet to be scientifically proven, but supplements with tyrosine can also help increase the levels of dopamine in the brain.
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Rice, M. E., Patel, J.C. & Cragg, S. J. (2011). Dopamine release in the basal ganglia. Neuroscience, 198: 112–137.