Key Difference – Dopamine vs Endorphins
Dopamine and Endorphin are chemical substances involved in the signal transmission within the nervous system. Both are known as neurotransmitters. The key difference between Dopamine and Endorphin is that Dopamine is a small molecule neurotransmitter which is mainly responsible for movements and feeling of pleasure while the Endorphin is a larger molecule of neuropeptide with the main function of pain relief.
CONTENTS
1. Overview and Key Difference
2. What is Dopamine
3. What are Endorphins
4. Side by Side Comparison – Dopamine vs Endorphins
5. Summary
What is Dopamine?
Dopamine (3,4-dihydroxyphenethylamine) is one of the neurotransmitters synthesized by the central nervous system. It acts primarily as an inhibitory neurotransmitter which is involved in balancing the brain stimulation from continuous excitement; it sometimes also acts as a neurohormone. Dopamine (C8H11NO2) is used as a precursor for the production of neurotransmitters: norepinephrine and epinephrine. This chemical is crucial for many functions in humans and animals. Some of the main functions of dopamine including pleasurable rewarding, movements, sleep, improvement of memory, mood fixing, focus and attention, behavior, learning, pain processing, regulation of prolactin secretion, etc.
Maintaining a proper concentration of dopamine in the body is important since low levels of dopamine lead to several diseases such as Tourette’s syndrome, schizophrenia, Parkinson’s disease, Huntington’s disease, drug addiction and depression. Parkinson’s disease is a severe disease caused by the deficiency of dopamine. It’s a progressive disorder in the nervous system which affects the movements of the body.
Figure_1: Chemical Structure of Dopamine
Once Dopamine is produced by the dopaminergic neurons as a response to a stimulus and is released to the chemical synapses, it diffuses through the synaptic cleft towards the postsynaptic dopamine receptors. There are five dopamine receptors found on the postsynaptic end: D1, D2, D3, D4 and D5. They are slow acting metabotropic receptors coupled with G proteins. After transmitting the chemical signal to postsynaptic neuron, Dopamine can be reuptaken and repackaged into synaptic vesicles by the presynaptic neuron or can be degraded by the enzymes.
What are Endorphins?
Endorphins are neuropeptides (a type of neurotransmitters) which mediate the signal transmission within the nervous system. Synthesis and storage of endorphins primarily occur in pituitary glands. Endorphin (C45H66N10O15S) release mainly happens due to the generation of the action potential by the stimuli: stress and pain. There are several major functions governed by endorphins. Those functions mainly include pain management, possessing morphine-like drug effects and reward system actions such as sex, feeding, drinking, etc. Endorphin binds with inhibitory G protein-coupled receptors called opioid receptors and reduces the perception of pain by inhibiting the synthesis of proteins involved in pain transmission. Therefore, endorphins can be considered as analgesics due to the pain killing ability. When endorphin secretions are low, it causes people to feel anxious and more susceptible to pains. High levels of Endorphin suppress pain and make you happy emotionally and physically. Endorphin secretion can be induced by proper exercises, meditation and by certain foods.
Figure 2: Endorphin Structure
What is the difference between Dopamine and Endorphins?
Dopamine vs Endorphins |
|
| Dopamine is a small molecule monoamine neurotransmitter. | Endorphin is a larger molecule neuropeptide. |
| Chemical Formula | |
| C8H11NO2 | C45H66N10O15S |
| Binding Receptor | |
| G protein-coupled D1 – D5 receptors | G protein-coupled opioid receptors |
| Body Functions | |
| Major functions include body movements, feeling of pleasure and motivation | Major functions income and overcoming stress and pain relief. |
| Medical Conditions | |
| This can cause Tourette’s syndrome, Parkinson’s disease, drug addiction, depression, etc. | This can cause moodiness, depression, and obsessive-compulsive disorder, etc. |
Summary – Dopamine vs Endorphins
Dopamine and Endorphin are neurotransmitters belonging to the neurotransmitter categories of monoamines and neuropeptides, respectively. Dopamine is a catecholamine while Endorphin is a larger molecule – a smaller protein composed of peptides. Both neurotransmitters are involved in the feeling of pleasure and the happiness, but, endorphins are mainly responsible for the mitigation of pain and dopamine is mainly responsible for body movements. This is the key difference between Dopamine and Endorphins. These two chemicals basically can be referred as happiness chemicals.
Reference:
1. “Multiple dopamine functions at different time courses.” Annual review of neuroscience. U.S. National Library of Medicine, n.d. Web. 13 Feb. 2017
2. Sprouse-Blum, Adam S., Greg Smith, Daniel Sugai, and F. Don Parsa. “Understanding Endorphins and Their Importance in Pain Management.” Hawaii Medical Journal. University Clinical, Education & Research Associate (UCERA), Mar. 2010. Web. 14 Feb. 2017
Image Courtesy:
1. “Beta-endorphin 1-9” By Edgar181 (talk) – Own work (Public Domain) via Commons Wikimedia
2. “Dopamine chemical structure” By Cacycle – Own work (Public Domain) via Commons Wikimedia
The word ‘endorphins’ is a truncation of ‘endogenous morphines’, and there is more than just one type. There are also enkephalins, which regulate nociception, or the sensation of painful or noxious stimuli, and there is also dynorphin, which has a role in sleep and appetite, but also plays a part in drug-seeking behavior because it can actually inhibit dopamine signaling.
I really enjoy your articles, Samanthi. Are you a doctor or a researcher?
Well thought out paper with concise points which clearly state the difference. Thanks