Neurons and Neurotransmitters A Brief

NEURONS AND NEUROTRANSMITTERS

Neurons and Neurotransmitters

Neurons, in basic terms, are cells (in particular nerve cells) responsible for the sending of messages across the body (Levin, Decker, and Butcher, 2012). They are considered to be the brain’s as well as nervous system’s fundamental units. To a large extent, they make it possible for a wide range of activities and functions to be performed including, but not limited to, walking, eating, talking, breathing and even thinking. Neurotransmitters, on the other hand, could be conceptualized as the substances that enable the communication between neurons, as well as communication between neurons and target tissues. More specifically, neurotransmitters have been defined by Avoli, Reader, Dykes, and Gloor (2012), as “endogenous chemicals that allow neurons to communicate with each other throughout the body” (173). As the author further points out, these endogenous chemicals play a significant role in the framing of our lives on a daily basis. This is more so the case given that thanks to the chemical synaptic transmission process, they enable the provision of a wide range of functions by the brain (Levin, Decker, and Butcher, 2012). The synaptic transmission process is, in essence, communication between neurons, as well as with target tissues.

There are various kinds of neurotransmitters. It is important to note that although there are more than 100 neurotransmitters that have been identified to date, it is possible that there are more neurotransmitters will be discovered in the future (Levin, Decker, and Butcher, 2012). To a large extent, it is the chemical nature of the said neurotransmitters that determines under which group they are placed. Towards this end, Avoli, Reader, Dykes, and Gloor (2012) point out that neurotransmitters could be categorized as amino acids neurotransmitters, monoamines neurotransmitters, peptide neurotransmitters, and acetylcholine, among others. Examples of amino acids neurotransmitters are glycine, gamma-aminobutryic acid (GABA) and glutamate. On the other hand, examples of monoamines neurotransmitters are norepinephrine, epinephrine, dopamine, histamine, and serotonin. Monoamines neurotransmitters are inclusive of endorphins.

In seeking to explore the working of neurotransmitters, it would be prudent to first point out that the human body comprises of billions of nerve cells. The said nerve cells, according to Avoli, Reader, Dykes, and Gloor (2012) consist of a cell body, an axon, and an axon terminal. According to the authors, the cell body comes in handy in the production of neurotransmitters and maintenance of nerve cell function. To ensure that the axon terminal receives electrical signals, the axon plays a crucial role. Further, to see to it that communication with the relevant organs, muscle cells, and nerve cells, the electrical message must be in the form of a chemical signal. The axon terminal, which is where neurotransmitters are located, is instrumental on this front as it is where the said conversion/change occurs. Neurotransmitters could be thought of as ‘couriers’ in a busy town that help in the transmission of information from one part of the town to another. In a more pronounced sense, the ‘couriers’ are responsible for the carrying of messages between neurons. When the need for a message to be sent from one neuron to another arises, a neurotransmitter is released into the synapse. A synapse, according to Avoli, Reader, Dykes, and Gloor (2012) could be defined as the communication/connection point between neurons. It is important to note that the messages transmitted by neurons could define one of three likely actions. Thus, in this case, Avoli, Reader, Dykes, and Gloor (2012) point out that we should think of modulatory neurotransmitters, inhibitory neurotransmitters, and excitatory neurotransmitters.

Following the delivery of the message, the synaptic cleft must cleared off the neurotransmitter molecules. In this case, the neurotransmitter could either diffuse (i.e. fade away), degrade (i.e. be broken down in such a way that it becomes impossible for it to engage in receptor cell binding), or be reabsorbed and utilized in what is known as the reuptake process.

It should be noted that in some instances, the working of neurotransmitters could be faulty or defective. An example of this is when the released neurotransmitter is either not enough or too much. One other factor that might get in the way of the effective working of neurotransmitters is synaptic cleft damage or inflammation that prevents the sufficient taking up of neurotransmitter by the cell receptors. Next, in some instances, the reabsorption of neurotransmitters could be too quick that it interferes with the effective working of a neurotransmitter.

In relation to the relationship between drugs and neural transmission, it would be prudent to note that it is via the alteration of neurotransmission that the body is influenced by drugs. In the words of Avoli, Reader, Dykes, and Gloor (2012), “some drugs mimic endogenous ligands, activating receptors directly; others interfere with reuptake, and some block receptors by binding to them without activating them” (301). In essence, changes to our behavior are founded upon how neurotransmission is altered by a specific drug. There are a number of ways through which messaging in the brain can be altered by drugs. One way is through the imitation of the natural chemical messengers. Another way could be via the binding of the drug to receptors in the brain. Messaging in the brain can be altered by drugs when drug chemicals overwhelm the brain by flooding it. Lastly, the drug could also overstimulate the brain’s reward circuit. According to Avoli, Reader, Dykes, and Gloor (2012) the brain’s reward system is often, in one way or another, usually affected (directly or indirectly) by drugs. It is the response of the brain that often results in addiction, essentially as a consequence of this reward system.