Why Does My Medication Work?

I started to research sertraline (the medication that I am taking) and depression when I wondered, what does this drug work? It was one of those moments that I have a general idea of something, but I have no idea what it really is. I hear and use words all of the time without even really knowing much about them. It is one of the things that I am working on because really thinking about the words we use daily is really important. 

And so, serotonin became one of those words or things, if you will, that I decided I should know more about. It comes up a lot in discussions about depression and other mental health discussions. On the surface, I know that researchers have found a connection between serotonin and depression. But why and how does it affect the way someone feels? I have to write that what I found is fascinating to me, and I hope to you. 

I have found that going back to the basics helps me. Finally! That almost undergrad minor in biology actually might help me. I have enough of a foundation to be dangerous, combining my base knowledge with the power of Google. One might say that my ability to connect those two things is one of my superpowers.

Our Brain’s Postal Office

The first piece to know is that within our brains are between 100 million and 100 billion neurons. ¹ Because neurons have both electrochemical aspects, they can transmit signals all over the body and at a great distance. Sending messages over several feet or several meters.² 

Our brain is continuously signaling to itself and the rest of the body so that we can exist in the world, and well, function. Without neurons, we wouldn’t even be able to stand up, let alone run marathons, drive cars, hold a loved one’s hand, etc. From the simplest to the most complex of tasks, neurons get us to the end result.

I think of neurons like post offices. Information comes into the neuron from other neurons; that information comes in, gets sorted, and then sent out to the next neuron until it gets it to where it needs to be. And so on and on. That transmission of information occurs more times than we may be able to count.

But neurons do not touch each other, so how does that information get from one neuron to another? Via the electrochemical messenger, the neurotransmitter.

Brain’s Postal Workers

The neurotransmitters move between the space between neurons. That space is called the synaptic gap.³ Based on what I read, it sounds like it is a small space. To us, it is small, but from the neurotransmitter’s perspective, it could look like the Grand Canyon. The synaptic gap is, I think, one of the reasons that neurotransmitters developed the way they did or that neurons developed the way they did. It is probably a chicken and egg conversation, as in, which came first? We may never know.

Without neurotransmitters, the information would not move along neural pathways to pass the information along.  Since I think of the neurons like post offices, I think of the neurotransmitters as postal workers delivering the mail. And that is why I draw them the way I do, hats and pouches, which represent postal workers. In case you were wondering what goes on in my head, now you know.

The intrepid neurotransmitters cross the synaptic gap, locate, and attach to a receptor site on the receiving neuron. Much like postal workers, neurotransmitters can only connect to specific receptors. There is a way that the neurotransmitters and the receiving neuron recognize each other.⁴ Maybe there is the electrochemical version of the secret handshake. That way, the wrong message does not accidentally get moved onto the next neuron. It’s like a postal worker had to find the right mailbox to deliver the message.

Serotonin – The Magical Neurotransmitter

If you guessed that serotonin must be a neurotransmitter, then you are correct. Serotonin is a recent discovery, only sixty years ago! And yes, in the science world, that is very recent. Scientists are still learning more about all of the serotonin areas in our bodies and brains. And so far, what they have found is that serotonin is involved in quite a few areas. 

The one area that serotonin is most famous for is in the brain, helping with mood regulation and memory. The lesser-known areas that serotonin is present within regulate normal bowel function and reduce your appetite as you eat to know that you are full. It is also why nausea is one of the side effects of taking medications that affect serotonin levels. And there are so many other areas that I have not listed here.

Serotonin also has a role in sleep. Although up for scientific debate, it would appear that it influences when, how much, and how well you sleep. Serotonin is needed to make melatonin. Melatonin is a hormone that also helps with sleep regulation. It makes sense then that not having enough or having too much serotonin can affect your sleep patterns. Dopamine and melatonin also help with sleep regulation.

It’s All Connected

It is no wonder then that some of the signs of depression have an underlying connection with serotonin. For instance, disrupted sleep or inability to sleep, overeating is another (I do). Because serotonin affects so many different areas, there is a very diverse use of specific drugs specific to serotonin.  

As scientists are continuing to discover, serotonin is present in many systems. It is still precise in regulating behavioral processes. And that is why there are such diverse uses of drugs that are specific to serotonin.⁵ 

Serotonin is much more than just a ‘feel good’ drug. Its role in other areas related to depression and other disorders makes it a massive deal for mental health. Dare I write, a much bigger deal than me, the non-scientist even considered.

Sources Cited

1. BrainFacts/SfN. The Neuron. April 1, 2012. BrainFacts. https://www.brainfacts.org/brain-anatomy-and-function/anatomy/2012/the-neuron#:~:text=The%20neuron%20is%20the%20basic,%2C%20an%20axon%2C%20and%20dendrites. Accessed October 8, 2020.
2. Craig Freudenrich, Ph.D.& Robynne Boyd “How Your Brain Works” 6 June 2001.
   com. <https://science.howstuffworks.com/life/inside-the-mind/human-brain/brain.htm> 21 October 2020
3. Kendra Cherry. “The Role of Neurotransmitters” December 7, 2019. Verywellmind.com .. https://www.verywellmind.com/what-is-a-neurotransmitter-2795394 October 10, 2020
4. W. McEnery, R.E. Siegal. “Neurotransmitter Receptors” 2014. Sciencedirect.com https://www.sciencedirect.com/topics/neuroscience/neurotransmitter-receptor October 19, 2020
5. Miles Berger, John A Gray, and Bryan L. Roth “The Expanded Biology of Serotonin: HHS Public Access ncbi.nlm.nih.gov https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5864293/ October 18, 2020