What is norepinephrine?
Norepinephrine is a neurotransmitter that is used by the sympathetic nervous system to send messages to other nerves and also muscle tissue.
Norepinephrine is also a hormone that is produced and secreted by the medulla (inner part) of the adrenal glands in direct response by nervous stimulation.
Norepinephrine causes blood pressure to rise, the heart to beat faster, increases metabolism and blood glucose levels, and increases energy production and blood flow to the extremeties.
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Important norepinephrine facts
- The amino acid tyrosine is a precursor to norepinephrine
- Dopamine needs to be synthesised to produce norepinephrine
- Norepinephrine is known as a neurohormone as it acts as both a neurotransmitter and hormone
- Norepinephrine is also known as noradrenaline
- Norepinephrine is a neurotransmitter of the adrenergic nervous system
- Norepinephrine stimulates the body systems to prepare to "fight or flight", which is a well-known human preservation reaction to any dangerous situations
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Why norepinephrine is important
Norepinephrine activates two types of cell membrane receptors:
- A-receptors - contracts smooth muscle (except in the intestines)
- B-receptors - relaxes smooth muscles; increases rate and force of heart muscle contractions
Norepinephrine is also an important neurotransmitter in many parts of the central nervous system, where it participates in blood pressure regulation, arousal and mood.
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references
- Marieb EM, Hoehn K. Human Anatomy & Physiology. 7th edition, 2006. Benjamin Cummings Publishing
- Tortora GJ, Derrickson BH. Principles of Anatomy & Physiology. 11th edition, 2005. Wiley Publishing
More information
To learn more, go to the following web sites
NOTE: Mega doses of any type of vitamin, mineral, amino acid or herbal supplement cannot cure illnesses and in fact can be very dangerous and produce toxic side effects and interfere with medicine you are taking. Always ensure you consult your doctor before taking any type of complementary supplements.
Disclaimer: This guide is not intended to be used for diagnostic or prescriptive purposes. For any treatment or diagnosis of illness, please see your doctor.
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