You have probably at one time heard of the role dopamine plays in feelings of pleasure or how serotonin influences depression. These are just but a few of the many roles neurotransmitters play in the body. Not only do they influence our mood, but they are responsible for regulating passive processes like digestion, breathing, and how our heart beats but also form the basis of higher cognitive processes like thinking and memory.
In this article, I will be giving an introduction into these chemical messengers, including what they are and their functions in the body.
What Exactly Are Neurotransmitters?
Neurotransmitters are chemical messengers that convey, boost, and balance signals being transmitted between neurons, or nerve cells, and other body cells. These chemical messengers can influence a lot of functions in our body – both psychological and physical, including sleep, heart rate, mood, appetite, cognition, love and fear.
In order to ensure the proper functioning of our brain, billions of neurotransmitter molecules are constantly working to help manage everything from our heartbeat to our breathing to our learning and concentration levels.
How Do They Work?
For neurons to send messages throughout the body, there is a need for them to be able to communicate with one another and transmit signals. Neurons form a web of connections in the brain and the body and at each of these connections is a synapse. The synapse is a specialised cell that allows communication between neurons. This process where the synapse is bridged so that signals can cross between neurons is called neurotransmission and what makes this possible are chemicals called neurotransmitters.
When an electric signal gets to the end of a neuron, it stimulates the vesicle which is a small sac containing the neurotransmitters. The vesicle pours its content into the synapse where it becomes easy for the neurotransmitters to bind and trigger changes in the cells. After the neurotransmitters are released, they cross the synaptic gap and attach the receptor on the other neuron. Depending on what the neurotransmitter is, it could either be inhibiting or exciting the receiving neuron.
They are classed into three groups
Neurotransmitters are majorly classified into 3 groups based on their function. They are classified as either excitatory neurotransmitters, inhibitory neurotransmitters, or modulatory neurotransmitters. The excitatory neurotransmitters produce an excitatory or stimulating effect on the receiving neuron – which means they increase the likelihood that the neuron will fire an action potential and the inhibitory neurotransmitters have inhibitory effects on the neurons meaning neurons are less likely to fire. There are also some neurotransmitters that can produce both an inhibitory and excitatory effect depending on the type of receptors on the receiving neurons.
Modulatory neurotransmitters, which are often referred to as neuromodulators are the category of neurotransmitters capable of affecting a larger number of neurons at the same time. Though they can be slow-acting, they also have the ability to influence the effects of other chemical messengers.
Important neurotransmitters and their functions
Since 1921 when the first neurotransmitter was first discovered, about 50 more neurotransmitters have been discovered. The details of the actions of all these chemical signalers could fill books, but I’ll give a top level overview of the functions of some of the primary transmitters.
Acetylcholine was the first neurotransmitter to be discovered. It was first isolated in 1921 by the German biologist, Otto Loewi who latter won a Nobel Prize for his work. Acetylcholine is produced in the body from choline, a nutrient that can be found in foods like seafood, eggs, and nuts.
This neurotransmitter is responsible for stimulating muscles. It gets the motor neurons controlling the skeletal muscles activated. Acetylcholine also regulates the activities in some parts of the brain, which are associated with learning, attention, arousal, and memory.
People suffering from Alzheimer’s disease are usually found to be low in Acetylcholine levels. Many poisons like curare, botulin, and hemlock act by blocking the acetylcholine receptors.
#3: Gamma-aminobutyric acid (GABA)
GABA is an inhibitory neurotransmitter that helps prevents anxiety by slowing down the activities of the neurons. his neurotransmitter is a non-essential amino acid that is synthesized from glutamate. When the levels of GABA become too low, it could result in anxiety disorders. Drugs like Valium acts by boosting the level of Gamma-aminobutyric acid.
Melatonin both acts as a neurotransmitter and a hormone. It is produced by the pineal gland and basically controls the sleep-wake cycle. Melatonin also controls sexual and mood behavior. Its production is significantly affected by light. While light to the retina could hinder its production, darkness has a stimulating effect on the production of the neurotransmitter.
Noradrenaline, also known as norepinephrine is an excitatory neurotransmitter that is both produced in the brain and secreted by the adrenal glands into the bloodstream. It has a multimodal set of functions in the body, being necessary for fight or flight response while being vital in the brain to promote concentration, vigilance and alertness and even enhance the formation and retrieval of memory.
Adenosine acts as neuromodulator in the brain and plays an important role in suppressing arousal and improves sleep. Adenosine is in fact one of the primary neurotransmitters involved in the initiation of sleep. Adenosine levels increase in the brain continuously during the awake cycle from the degradation of adenosine triphosphate (ATP), the molecule is involved with regulating the body’s various cellular energy functions. The levels of adenosine decrease while you sleep and then give the signal to awake. The modern world’s best friend, caffeine acts by blocking the action of adenosine, thereby stopping your body feeling tired.
Glutamate is another excitatory neurotransmitter that functions in ensuring homeostasis with the effects of GABA. It is the most abundant neurotransmitter in and also acts as the central nervous system’s primary excitatory neurotransmitter.
However, excessive levels of glutamate also have a toxic effect on the nerve cells and may lead to conditions like stroke. Glutamate is naturally abundant and found in foods like tomatoes, cheeses, mushrooms, seaweeds, and soy.
Histamine functions as a neurotransmitter in the brain as well as in the spinal cord. It is involved in allergic reactions and also has a role to play as part of the immune system response to pathogens.
Nootropics and their actions in the body
Nootropics are a class of medication or supplement used to enhance cognitive performance. Humans have been using Nootropics for millennia whether it be tea or coffee or other herbal extracts. Today there are a variety of very potent pharmaceutical Nootropics such as Modafinil or Ritalin available and of course many potent supplements and herbal extracts standardized to a percentage of the major active ingredients such as Bacopa extract with 50% Bacosides.
Listed below are some typical actions nootropics can have on the body.
- Increase neurotransmitter production: Nootropics have a powerful effect on the brain because they alter the regulation of neurotransmitters. Some of them also increase production rate of neurotransmitters in the brain. For instance, some herbs like bacopa and Rhodiola can stimulate the body to produce more neurotransmitters.
- Decrease neurotransmitter reuptake: nootropics also acts by directly decreasing reuptake of some nutrients like mono-amines as it is seen in Modafinil, Rhodiola, and anti-depressants. By decreasing the reuptake of the neurotransmitter in the brain the chemical acts to increase or regulate the level of neurotransmitter in the recipients brain.
- Replace precursor nutrients: Neurotransmitters require the presence of the precursor nutrients in the brain. Replenishing the precursor nutrients allows the brain to operate effectively where otherwise performance may suffer. The primary action of WorkWize is to replace the catecholamine precursors tyrosine and phenylalanine to help fight fatigue.
- Support brain growth: Some nootropics help increase growth-supporting factors in the brain, such as brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF). These two factors are important in regulating the growth and function of brain cells.
- Neuroprotective: Nootropics can have neuroprotective properties that help ward away age-related cognitive decline and keep your brain healthy even into your later years.
- Enhance blood flow: Some nootropics supports the flow of blood throughout the brain, helping you stay sharp and alert. It also supplies your brain with oxygen and other vital nutrients to help fight disease and mental fatigue.
- Anti-inflammatory: Some nootropics contain powerful antioxidants which help reduce inflammation in the brain. Reducing inflammation in the brain reduces the likelihood of various diseases including cancer.
The Bottom Line
Neurotransmitter are chemicals the body uses to regulate nerve signal transmission in the body. They are created in the neurons from precursor nutrients delivered to the neurons from the blood. There are many neurotransmitters in the body and our knowledge of them continues to grow, there are over 50 of them known at this point. Nootropics are a class of compound that can affect the neurochemistry of our brains. There are many ways Nootropics can help brain health, they can support brain cell growth, increase blood flow, and have neuroprotective and anti-inflammatory properties. Nootropics an also affect the level of neurotransmitters in the brain. Nootropics can increase or regulate the level of specific neurotransmitters through several actions; they can decrease the reuptake (reabsorption) of the neurotransmitter, they can increase the production rate of neurotransmitters in the brain and they can supply more of the fuel required to create the neurotransmitters in the brain. Increasing the level of available neurotransmitters in the brain thus allowing the brain to send more of the signals that the neurotransmitters produces.