09 January 2013

Brain chemistry uncovered

Neurotransmitters are the temperamental little critters that you need to have exactly the right amount of, and in the right locations, to keep the lights burning.


Neurotransmitters – a group of brain chemicals – are the temperamental little critters that you need to have exactly the right amount of, and in the right locations, to keep the lights burning. 

When your GP or psychiatrist prescribes a certain psychiatric medication he or she mostly aims to establish the right amount of each type of neurotransmitter in your brain and body. Achieving this chemical balance is a finely tuned process as every person has a unique neurological profile.

Also, as neurotransmitters are involved in brain activity, they can’t merely be counted in the same way as, say, red blood cells. Measuring their activity in the blood doesn’t provide useful information about brain function.

You may have seen neurotransmitter tests advertised online, but Professor Dan Stein, Head of Psychiatry at UCT, indicates that there is no data showing that such tests are useful in the evaluation or treatment of mental illness.

By having an understanding of how neurotransmitters function in your body, you may assist your doctor in determining the right dosage and type of medication. Every combination of neurotransmitters affects a specific aspect of emotion, thinking and behaviour.

By noting the effects on your brain and body, you may provide valuable feedback to your doctor, thereby helping to establish a suitable ‘balance’ of neurotransmitters needed for your mental wellness.

What are neurotransmitters?

Neurotransmitters are minute and complex chemical compounds found in the spaces where your nerves connect. You will have heard these names before: dopamine, melatonin GABA, ACh and 5-HT.

Their real names are to the lay ear, and I bet to half of health professionals too, an unpronounceable impossibility. Just try saying N-trimethylethanaminium!

The scientific name for a neurotransmitter will be one that describes the different parts of its chemical composition. In everyday terms, neurotransmitters are mostly known by their acronyms – N-trimethylethanaminium (also known as acetylcholine) for instance becomes Ach, and 5-HT refers to a component of serotonin. Serotonin is likely the best-known neurotransmitter as it plays such a central role in treating depression.

There are well over a 100 types of neurotransmitters – located not only in the brain, but in places all over the body. Interestingly, more serotonin will be found in your gut than in your brain.

Neurotransmitters move along or in-between nerves and nerve endings. When travelling along the nerve, they are packed into pouches referred to as vesicles in which they move towards the synapse. A synapse is the contact area or junction between the various nerve cells (neurons) of the nervous system.

Acetylcholine was the first neurotransmitter to be envisaged back in 1921. In 2010, a clear image of a synapse was obtained for the first time. One of the challenges in taking a photo of a synapse (apart from it being so small) is that it is forever moving. However, by using a newly developed rapid ‘freezing’ technique, scientists managed to obtain an image, showing the vesicles, the synapse and cell walls.


               A 3D model of the neurotransmitter serotonin

How do neurotransmitters operate?

To get a mental picture of this complex process, you may well want to put on your 3D glasses! Think of it this way: your postman swims across a canal, letter bag over his shoulder. A DHL courier crosses the canal on a ferry and somewhere in between, is Chad Le Clos with a parcel on his back.

The canal is the synaptic opening – the space between nerve endings – and on the other side of the canal a multitude of mail guys are awaiting the deliveries. Each is holding a mail bag (receptor) matching the exact size, shape and colour of one of the parcels the swimming postmen and couriers are delivering to them. The swimming postmen and couriers will keep searching until they find the matching bag in which their parcel will fit.

It doesn’t stop there though. The mail guys will only carry the parcel to the next canal (synapse), and the whole process repeats. Certain routes (neuronal tracks) exist for specific ‘parcels’; the end result being the activation of a specific area of the brain or body.

Neurotransmitters therefore are messengers or couriers taking a command from the one nerve ending to the next, across the synaptic cleft. Sometimes the contents of the bags spill into the canal. The postman may then quickly gather it and take it back to the shore it came from (the so-called reuptake in SSRI’s). Or it will simply dissolve in the water and become fish food.

The complexity

Thinking of neurotransmitters in this simplified way shows the importance of the exchanging and matching of different chemicals at the synapse. However, if you take into account the numbers involved in this exchange process, you can begin to appreciate its true complexity.

There are at least 300 billion such ‘canals’ to be crossed and there are more than a 100 types of neurotransmitters at work. On top of it all, it’s a relay race, which also depends on the conditions of the canals - and the ‘mail men’ take only a few milliseconds to deliver their parcels and clear-up any spillages. Yes, it is an amazing race indeed! No wonder things can sometimes go awry.

The biological phenomenon of a synaptic cleft, where different chemical substances can be relayed to several destinations, enables a complex set of behavioural combinations.

Having these intricate interactions occur in the right place and at the right time, enables a person to choose from (or to at least experience) an optimised number of possible reactions. This gives us humans the ability to adapt to our world in the best possible way.

(Engelie Brand, MSc, Clinical Psychologist, Thrive magazine) 

This article was first published in the launch issue of Thrive Magazine– Your Guide to Mental Wellness. Thrive is available for free from Pick n Pay Pharmacy or view online at . 


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