Neurotransmitters…What?

What are neurotransmitters?

Let’s say that you want to make a phone call. You need to decide who to call, think about what to say, pick up the phone, find the number, punch in the number, listen for a ring, say hello, talk to the person, listen to the person, respond to what they say, end the call, and put down the phone.

All this happens without you even thinking much about it. But a great deal is happening in your brain. Our brains have billions of nerve cells. With an act as simple as making a call, many of these cells connect with each other. They connect using your neurotransmitters.

Neurotransmitters are your brain and body’s chemical messengers. They carry messages from one part of your brain or body to another. These messages allow you to move, talk, feel, learn, think, see, hear, and do many other tasks, including breathing. Without neurotransmitters, you would not exist.

Your brain and body have a huge network of nerves. Nerves send signals throughout your brain and all over your body. Nerves are involved in everything you do. Neurotransmitters carry chemical signals from one nerve cell to another or to other types of cells such as muscles or glands.

How do neurotransmitters work?

Nerves have a cell body and a long attachment called an axon. The axon carries electrical signals down the nerve. At the end of the axon is the axon terminal. This is where the neurotransmitters live. They are stored in sacs called synaptic vesicles. Each vesical contains thousands of neurotransmitters.

When the electrical signal reaches the end of the axon, it releases the neurotransmitters from the axon terminal. Neurotransmitters carry the message across a fluid area to another nerve, a muscle, or a gland. Each type of neurotransmitter connects with a specific type of receptor. It is like a key that can only work on its partner lock. The neurotransmitter then triggers a change in the target cell. It might cause an electrical signal in another nerve. It might also cause a muscle to contract or a gland to release a hormone.

What actions do neurotransmitters cause in cells?

Neurotransmitters lead to one of three possible actions. First, they can “excite” the next cell to continue to pass on messages. Second, they can “inhibit” or block the signal from continuing. Third, they might “modulate” or adjust how nerves communicate with each other. In other words, they can fire up, calm down or adjust our system.

What are the different types of neurotransmitters?

We know of at least 100 neurotransmitters and there are probably many more we don’t know about.

Here are a few examples:

• Glutamate is the most abundant neurotransmitter in your brain. It is an excitatory neurotransmitter. It “excites” other nerves. It is important for learning and memory. People with Alzheimer’s disease, Parkinson’s disease and seizures may have imbalances in glutamate.
• Gamma-aminobutryic acid (GABA) is also abundant in your brain. It is an inhibitory neurotransmitter. It helps prevent problems such as anxiety, irritability, sleep disorders and depression.
• Serotonin is an inhibitory neurotransmitter that regulates mood, anxiety, appetite and pain. Commonly used medications called selective serotonin reuptake inhibitors (SSRIs) may be used to increase serotonin levels for people with depression or anxiety.
• Dopamine is important in your brain’s reward system. It helps with feeling pleasure. It also helps with concentration, memory, sleep, mood and motivation. Disorders of dopamine neurotransmitters include schizophrenia, bipolar disorder, and attention deficit hyperactivity disorder (ADHD). Stimulant drugs such as Ritalin and Adderall act on dopamine. Cocaine also acts on dopamine.
• Epinephrine (also called adrenaline) and norepinephrine (noradrenaline) lead to your “fight-or-flight response” to fear and stress. They increase your heart rate, breathing, blood pressure, blood sugar and blood flow to your muscles. They also increase your alertness and attention.
• Endorphins are your body’s natural pain reliever. Release of endorphins reduces pain. Exercise releases natural endorphins.

These are just a few of our neurotransmitters. There are many more. We have much to learn about how they all work and how they interact with each other. The human brain is exceedingly interesting and complex. Think about that next time you make a phone call.