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There is another page describing the endocrine system and the hormones that influence the  body’s activity.  A healthy endocrine system is highly important for a healthy body.  The endocrine system is also known as the “vital” body.  It is an electro-chemical system.  Nerves transmit electrical impulses, and chemicals determine just how efficiently the electrical system works – the neurotransmitters.

There are neurotransmitters and receptors across each neuron, and one neuron connection will often function with multiple types of neurotransmitters.  Just what information is transmitter across a neuron depends on what type of neurotransmitter is released.  There are several classes of neurotransmitters:

  • Amino acids such as Glutamate and GABA.  Glutamate is needed for synthesizing proteins, and GABA is an inhibitory neurotransmitter needed for muscle operation.  These are very common neurotransmitters throughout the human body.
  • Peptides such as opioids, substance-P, cocaine and amphetamine transcript (CART).  The brain produces some of these substances which are very similar to externally ingested drugs that have similar names.  These have a role to play in handling stress and pain.  The runners high is due to the release of endocannabinoids during prolonged physical activity (endorphins).  It is a much safer way of getting high, with the handy by-product of also keeping you fit!  It is still possible to become addicted to the drugs that your own body produces.
  • Gasotransmitters such as Nitric Oxide (NO).  This has a short lifetime (a few seconds) and is used for signalling in the body.  In Jana Dixon’s book “The Biology of Kundalini” she suggests that Nitric Oxide in the blood may be one of the mechanisms associated with the feeling of Kundalini energy rising up the spine.
  • Acetylcholine, used for nerve signalling to the muscles.
  • Monoamines such as dopamine, norepinephrine, adrenaline, histamine and serotonin.  These are really important (check out the diagram below).  Histamine is associated with the immune system and is the one responsible for people with hay fever, asthma or other allergies.  Allergies are an over-reaction of the immune system to a particular stimulus or detection of a foreign body.  The reaction we have to the cold virus is also a histamine over-reaction – the fever from the cold is often minor compared to what we have to deal with the over-reacting mucus membranes. It seems that our bodies always like to be over-reacting to some external stimulus; it just manifests differently between individuals.  It is probably the result of evolutionary selection, where those individuals that didn’t over-react to these external stimuli were more likely to die.  Epinephrine (or adrenalin) is produced in the adrenal glands in response to stress and negative feelings.  One of the issues in the busy western world is that many people are in a state of almost constant stress resulting in an over-production of adrenalin and tired adrenal glands.  Occasional subjection to stress is okay, but a continual low-level exposure to stress is not okay.


These three – Dopamine, Norepinephrine and Serotonin – have a major impact on our motivation and happiness.  It is the balance of these three that are targeted by anti-depressive drugs through selective re-uptake inhibitors (SSRI’s).  Dopamine keeps us alert and motivated; too little results in us being distracted and confused (Dementia is due to lack of dopamine).  Norepinephrine helps us concentrate and remember things – a deficit means distraction and confusion.  Serotonin helps us feel relaxed and contented.  A deficit of serotonin leads to depression.

Drugs like Cocaine act as re-uptake inhibitors, leading to a short-term high, and painful withdrawal symptoms.  Meditation and yoga help to increase the Serotonin levels in the brain.  Serotonin supplements do not cross the blood-brain barrier, but supplements such as 5-HTP, which is used in the synthesis of Serotonin, can be derived from foods such as Turkey (which is high in Trytophan) or from vitamin supplements.  These may help indirectly to increase Serotonin levels.  Melatonin is in turn sythesized from Serontonin.

We are not taught in School how to create and balance these vital brain chemicals.  We just assume that are bodies will do it for us, and it doesn’t always go well.  An imbalance typically results in mental and behavioural problems and general discontent and unhappiness.  Meditation and other spiritual practices will help to balance these important neurotransmitters, but note that it takes practices and is a long-term health benefit.  Drugs from your health professional may be required to urgently fix severe depression or other mental issues.