Neurotransmitters are chemical messengers in the brain that send signals from one neuron to the next. These signals are sent either to other neurons (interneurons) or to other parts of the brain itself (reticular formation).
There are many neurotransmitters, and they each have different functions. Some neurotransmitters increase anxiety, while others decrease it. Some neurotransmitters make you feel happy, and some make you feel sad.
The way these chemicals work is by binding to receptors located on the surface of the brain cells. This binding triggers a response in the cell, usually transmitting a signal to another cell.
Because there are different neurotransmitter receptors, only certain chemical messengers can unlock them. If a neurochemical doesn’t match up with the receptor, then no transmission will occur. It is like a locked door that only certain neurochemical keys can unlock.
Structure of a neurotransmitter
A neurotransmitter’s structure is part of what determines which receptors it can bind to and what effects it can have.
For example, dopamine molecules have a specific shape that allows them to bind to particular receptors. If the molecule shape is changed in any way, it cannot bind to the receptor and produce an effect.
Certain drugs used to treat schizophrenia work by blocking the D2 receptor. This prevents dopamine from binding there, which then reduces some of the symptoms of schizophrenia.
By selectively targeting specific structures, drugs can have very specific effects on the body and brain. This is why there are so many drugs available; each one targets a different neurotransmitter or collection of neurotransmitters with a unique structure.
Whether a drug is effective or has negative side effects depends heavily on how well it matches up with the structure of the targeted neurotransmitter or transmitters.
Examples of neurotransmitters
Neurotransmitters are the chemical messengers in your brain that communicate information between neurons.
There are a number of different neurotransmitters, and each one functions in a specific way. Some neurotransmitters allow communication between neurons to occur, while others inhibit communication.
Neurotransmitter receptors are located inside of the nerve cell walls. They function like door locks within the cell. Only certain neurotransmitter keys can unlock these receptors, which allows information to be transmitted through the cell.
Prozac is a selective serotonin reuptake inhibitor (SSRI) which works by preventing the reuptake (recycling) of serotonin in the neuron. This leaves more serotonin available to bind to the receptor and transmit information through the cell membrane.
Adrenaline is like the key that unlocks the stress response structure. When you experience a stressful event, your body releases adrenaline, which stimulates various systems and functions in your body.
These include: increased heart rate, blood pressure, respiratory function, and metabolism. All of these help you respond to the event by either fighting or fleeing the situation.
Adrenaline is a neurotransmitter that activates cortisol, which is part of the stress response system. As mentioned before, cortisol has many negative effects on your body when it is circulating in high levels.
When you are able to control how much adrenaline is released in your body, then you can control how much cortisol is released as well.
If you are constantly experiencing stressful events then your body will become immune to the effects of adrenaline and cortisol. This means that you need higher levels of them to achieve the same effect.
Noradrenaline is also called norepinephrine. This neurotransmitter is important for focus, attention, motivation, and mood.
People who suffer from low noradrenaline experience symptoms like poor concentration, lack of motivation, and depression. However, if more noradrenaline is available, the body can produce more excitement and stress.
There are drugs that target noradrenaline receptors to help people with low concentrations of this neurotransmitter. These drugs have some unpleasant side effects, though.
The most common one is weight gain due to changes in metabolism. Another one is vaginal dryness, which makes it harder to have sex. Interestingly, women make the same drugs that target noradrenaline receptors but in lower doses because their bodies already produce enough of the neurotransmitter.
Whether we are male or female seems to affect how our bodies handle certain drugs.
Dopamine is the neurotransmitter that controls the reward and pleasure center in the brain.
It is responsible for our feelings of satisfaction and happiness. When we experience something that makes us feel good, dopamine is being released.
This makes us want to repeat that experience, because it makes us feel good. This is why we prefer things that make us happy and give us satisfaction- we like them because they make us feel good and we want to keep feeling that way.
Dopamine is involved in addictive behaviors, including alcohol addiction, drug addiction, and gambling addiction. When someone experiences something new that they find pleasurable, their brain responds by releasing dopamine.
This explains why people find new things enjoyable– they are receiving a boost of dopamine. People who are addicted to things are actually suffering from a dopamine deficiency. Finding things that increase dopamine can help relieve this.
The final common neurotransmitter is serotonin. Serotonin is known as the happiness chemical due to its role in mood.
Serotonin is released by nerve cells in the brain. It travels along neurons to receptors on other neurons, where it passes on the signal.
Like acetylcholine, serotonin operates in two ways: non-nerve and nerve transmission. Non-nerve transmission occurs when serotonin is released in the blood circulation system. Nerve transmission occurs when serotonin is released at a nerve terminal which then connects with another nerve cell.
Just like acetylcholine, there are many different receptors that serotonin can bind to on the surface of a cell. What effect it has depends on what cell it encounters and what receptor it binds to. How does this knowledge apply? Some research suggests that certain disorders may be linked to changes in the function of these receptors.
A neurotransmitter called histamine is like a locked door that only certain neurotransmitters can unlock. Histamine is a chemical that cells in your body use to communicate with each other.
There are several types of histamine receptors in the brain, and these receptors are found in two main places: the outer part of the brain (the cortex) and the lower part of the brain (the hypothalamus).
When histamine is released in the brain, it activates the histamine receptors, causing some effect. For example, it might make you feel sleepy or relaxed. It might also affect your appetite and your metabolism.
Certain drugs act on histamine receptors to reduce symptoms of illness. These are called anti-histamines, which you might recognize as a common drug used to treat symptoms of allergies. Antihistamines block histamine from activating its receptor and producing its effect.
Another important neurotransmitter is acetylcholine. Acetylcholine acts in the parasympathetic nervous system and is involved in the regulation of muscle activity, including blood pressure.
Acetylcholine is a chemical that sends messages from one nerve cell to another nerve cell or to a body organ. When a nerve cell receives a signal from other nerves or from its brain region called the spinal cord, it responds by releasing acetylcholine.
This neurotransmitter triggers a response in the next nerve or body organ. Acetylcholine can either make a body organ or nerve cell relax, or make it contract. It does this by connecting with special receptors on these cells that affect what they do.
Acetylcholine is produced in special cells in your brain called neurons. These neurons send acetylcholine messages to every part of your body through our nervous system.