What is the Difference Between Serotonin and Endorphins

The main difference between serotonin and endorphins is that serotonin is responsible for mood and well-being whereas endorphins are responsible for stress relief.

Serotonin and endorphins are two substances produced by the body to make a person happy. Both of them, along with dopamine and oxytocin, are happy hormones.  

Key Areas Covered

1. What is Serotonin
     – Definition, Structure, Function
2. What are Endorphins
     – Definition, Structure, Function
3. Similarities Between Serotonin and Endorphins
     – Outline of Common Features
4. Difference Between Serotonin and Endorphins
     – Comparison of Key Differences

Key Terms

Serotonin, Endorphins

What is Serotonin

Serotonin or 5-hydroxytryptamine (5-HT) is a monoamine neurotransmitter with a complex biological function in modulating mood. It also has a function in sleep, digestion, nausea, wound healing, bone health, blood clotting, and sexual desire. In addition, serotonin can also act as a hormone. Serotonin mostly occurs in the enteric nervous system of the gastrointestinal tract. It occurs in the raphe nuclei located in the brainstem, Merkel cells in the skin, pulmonary neuroendocrine cells as well as taste receptor cells in the tongue. Blood platelets also store serotonin.

Figure 1: Serotonin

The main function of serotonin is to regulate mood. Generally, it is the body’s natural “feel good” chemical. Serotonin causes one to feel more focused, happier, emotionally stable, and calmer at normal levels. However, low levels of serotonin are associated with depression. Many medications that treat anxiety and depression increase the serotonin levels in the brain.

What are Endorphins

Endorphins are hormones the body releases during pain and stress. They are endogenous opioid neuropeptides. Generally, the pituitary gland produces and stores endorphins. The three types of endorphins are α-endorphin, β-endorphin, and γ-endorphin. Noradrenaline increases the production of endorphins. The main function of endorphins is to reduce the communication of pain signals. It binds μ-receptors of peripheral nerves, blocking the neurotransmitter substance P that occurs in the brain.

Figure 2: α-Endorphin

Moreover, endorphins reduce stress, relieve pain, and improve the sense of well-being. Other functions of endorphins include easing the symptoms of depression, helping with stress and anxiety, improving self-image, contributing to weight loss, alleviating childbirth pain, etc.

Similarities Between Serotonin and Endorphins

• Serotonin and endorphins are two substances produced in the brain.
• They are responsible for making a person happy.
• Moreover, both can act as hormones.

Difference Between Serotonin and Endorphins

Definition

Serotonin refers to a chemical messenger that’s believed to act as a mood stabilizer while endorphins refer to the chemicals (hormones) that the body releases when it feels pain or stress.

Type

Serotonin is a neurotransmitter while endorphins are neuropeptides.

Production

The production of serotonin occurs in the intestinal tract and the central nervous system while the production and storage of endorphins occur in the pituitary gland.

Precursor

The precursor to serotonin is indoleamine while the precursor of endorphins is proopiomelanocortin.

Storage

The storage of serotonin occurs in blood platelets while the storage of endorphins occurs in the pituitary gland.

Types

The two types of serotonin are the serotonin produced in the enteric nervous system and the serotonin produced in the central nervous system while the three types of endorphins include α-endorphin, β-endorphin, and γ-endorphin.

Mechanism of Action

Serotonin occurs in the enteric nervous system, central nervous system, and platelets while endorphins inhibit the transmission of nerve signals.

Function

The functions of serotonin include mood, sleep, digestion, nausea, wound healing, bone health, blood clotting, and sexual desire while the functions of endorphins include helping relieve pain, reduce stress, and improve the sense of well-being.

Conclusion

In brief, serotonin and endorphins are two types of hormones in the body that are called happy hormones. 90% of serotonin occurs in the enteric nervous system and the rest occurs in the central nervous system and platelets. Generally, serotonin is a neurotransmitter that can act as a hormone. The main function of serotonin is to stabilize mood, sleep, digestion, and nausea. It also helps in wound healing, bone health, blood clotting, and sexual desire. In contrast, endorphins are neuropeptides that are the hormones produced in the pituitary gland. There are three types of endorphins: α-endorphin, β-endorphin, and γ-endorphin. The main function of endorphins is to help relieve pain, reduce stress, and improve well-being. Therefore, the main difference between serotonin and endorphins is their structure and function.

References:

1. “Serotonin: What Is It, Function & Levels.” Cleveland Clinic, 
2. “Endorphins: What They Are and How to Boost Them.” Cleveland Clinic, 

Image Courtesy:

1. “Serotonin-2D-skeletal” By CYL– Own work (Public Domain) via Commons Wikimedia
2. “Alpha-endorphin” By Ed- Own Work (Public Domain) via Commons Wikimedia