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Endorphins are natural chemicals in the body that fight pain. Endorphins are released when a person gets hurt, but also during exercise, laughter or sex. In addition to blocking pain, endorphins can make people happy.
Endorphins resemble drugs like morphine, so when scientists first discovered these chemicals in the 1970s, they termed them "endogenous morphine." Since then, scientists have identified and named five different types of endorphins, all of which occur naturally in the body. Endorphins can also be found in most animals.
Types[change | change source]
Four types of endorphins are created in the human body. They are named alpha (α), beta (β), gamma (γ) and sigma (σ) endorphins. The four types have different numbers and types of amino acids in their molecules; they have between 16 and 31 amino acids in each molecule.
Beta-endorphins (β-endorphins) are the most powerful endorphins in the body. They are usually in the hypothalamus and pituitary gland. More endorphins are released in the pituitary gland during times of pain or stress. Exercise increases the endorphin release too. For the same reason, exercise results in a better mood.
Met-enkephalin and leu-enkephalin are in the brain stem and spinal cord; they are the pain killers of the spinal cord. Both of them have five amino acids in their structure; the first four are similar, but the last one is different.
Action[change | change source]
All of the endorphins bind to the opioid receptors in the brain. Many of the analgesic (pain killer) drugs have a similar action in the brain. The main difference between the natural endorphins and the analgesic drugs is that natural endorphins are cleared from the blood very quickly. Endorphins are also involved in the release of sex hormones in the pituitary gland. Also, scientists think that acupuncture results in the release of more endorphins. Endorphins may have a role in obesity, diabetes and psychiatric diseases too.
Endorphin rush[change | change source]
The term endorphin rush is sometimes used in normal speech to refer to a feeling of wellness caused by exercise, danger or stress. However, it is not a medical term, and it is not proven that higher endorphin production after exercise really has a role in the wellness feeling.
Another term which is commonly used is runner's high. It refers to the feeling being "high" (full of energy and wellness) after exercise. It is commonly said that the "high" is a result of the release of bigger amounts of endorphins in the body during the exercise. However, some scientists think this feeling is caused by the challenge, and is not related to endorphin release.
For example, in some studies a drug was given to people which blocked the effect of endorphins. These people still felt the runner's high; it means this feeling is not caused by the release of endorphins in the blood. Another study was performed in 2004, which showed this feeling is related to a different body chemical named "anadamide". Anadamide is not an endorphine but is an endocannabinoid, similar to one of the chemicals in marijuana.
References[change | change source]
- Guyton, AC; Hall, JE (2001). Textbook of Medical Physiology (10th ed ed.). WB Saunders. pp. 556.
- Bancroft, J (Sep 2005). "The endocrinology of sexual arousal.". The Journal of endocrinology 186 (3): 411-27. PMID 16135662.
- Best, Ben. "Brain Neuron Physiology". http://www.benbest.com/science/anatmind/anatmd1.html. Retrieved 2007-10-07.
- Dalayeun JF, Norès JM, Bergal S (1993). "Physiology of beta-endorphins. A close-up view and a review of the literature". Biomedicine & pharmacotherapy 47 (8): 311-20. PMID 7520295.
- "Runner's high". University of Pittsburgh Medical Center. http://www.sportsmedicine.upmc.com/MySportRunningHigh.htm#Endorphin. Retrieved 2007-10-18.
- Hinton E, Taylor S (1986). "Does placebo response mediate runner's high?". Percept Mot Skills 62 (3): 789-90. PMID 3725516.
- "Study links marijuana buzz to 'runner's high'". CNN. 2004-01-11. http://www.cnn.com/2004/HEALTH/01/11/marijuana.exercise.reut. Retrieved 2007-10-18.