Cocaine And Dopamine example essay topic

Well written Essay on Cocaine's effect on the brain It is used in offices, parties, on street corners, in homes, and even in schools. With so much wide-spread abuse, cocaine is in extreme demand. Cocaine abuse has risen 118% since 1990, and continues to rise (World Book Enc. ). Cocaine addiction is easy to understand- it [cocaine] produces a good feeling, so naturally people would tend to want more of it.

The question now though, is: how does it produce these feelings, and why is the addiction so strong. By taking a look at cocaine from it's entrance into the body, to the end of it's high, and the side-effects it produces, the answers to these questions will become clear. Cocaine comes in two forms-preprocessed and cut (which is the most popular, and most expensive on the market), or in rock form which is most commonly called 'crack'. Cocaine is taken mainly in two ways: inhalation, and injection (Encarta '96).

When inhaled, cocaine travels up through the nasal passage to the capillaries that line the olfactory nerves. This provides a more direct route to the brain than an injection and gives what is commonly referred to as a 'quick high'. The olfactory nerves will receive some of the cocaine particles and mistake them for smell-producing particles. The cocaine will enter the nerve and eat away at it, and in time, will destroy it, leaving the victim with no sense of smell (Drugs and the Brain). Cocaine needs to be in the bloodstream to become effective. Whether through the nose capillaries, or an injection, once the cocaine is in the bloodstream, it will travel to the brain.

Cocaine particles bear a striking resemblance to glucose molecules, so as they enter the brain, the hypothalamus will send messages to the brain to open more dendrical receptors to receive the overflow of "glucose" (Enc. of Drug&Alch. Abuse). Glucose naturally induces the production of th neurotransmitters dopamine and seretonin. This is commonly referred to as a 'sugar rush', so as the cocaine enters the dopamine and seretonin receptors, the brain believes it's on a 'sugar rush' (Enc. of Drug&Alch. Abuse).

As cocaine floods the dopamine and seretonin receptors to there limits, the hypothalamus will send signals to open more receptor sites. They are most commonly those of norepinepherine and noradrenaline (Guide to Psychiatric Drugs). The production of seretonin (the neurotransmitter that slows down the system) is blocked by cocaine, and dopamine (the neurotransmitter that excites the system) is produced rapidly. The excess dopamine flows into the open receptor sites of norepinepherine and noradrenaline (the neurotransmitters that arouse and cause pleasure) and excites them. This creates the "rush" that cocaine gives it's abuser. After repeated usage of cocaine, the brain begins to fall prey to an effect called neuro adaption (Enc.

Drug&Alch Abuse). The neurotransmitters start to adapt to the dopamine overflow and seretonin receptors will die off and seretonin will not be produced at it's normal levels in the brain. This adaptation will require more of the drug to produce the previous effect, and the once thought amount of cocaine needed to produce a high will be needed to produce a norm. This dependence is called a physiological dependence, and is common with repeated cocaine abuse (Text Book). Cocaine will often cause death in it's users. Most often heart attacks and strokes occur, convulsions are produced at the least.

The rush of dopamine and drop of seretonin is taking place all over the brain. All the activity caused by this, depreciates the clarity of normal messages of thought and sense from region to region of the brain. The most often clouded messages are those from the brainstem to the subcortex (Enc. Drug&Alch Abuse).

When the hypothalamus reads low levels of adrenaline, it sends messages to the medulla to increase heart rate. The medulla relays the message to the pituitary gland for production of adrenaline, but due to the high levels of dopamine, the message for an increase in a hormone produced by dopamine called prolactin is read as well. Prolactin and adrenaline are produced in the adrenal glands. As the hormones enter the heart, they increase heart rate to abnormal highs. The heart will become exhausted by the abnormal overuse.

Incoming messages to the brain are slow and clouded, so the medulla continues to send messages for increased heart rate until a heart failure occurs. Strokes and convulsions occur mainly due to dopamine flowing into the wrong receptor sites. This rush is too much and malfunctions start to occur in the motor cortex, producing convulsions and in some cases, strokes and deaths. (Enc.

Psychoactive Drugs) Surprisingly, the Limbic System, or that which produces emotion in the brain, is not affected by cocaine as was once believed. Recent studies indicate that the relaxed, euphoric feeling that is produced is achieved during a high is created by the clouded messages that occur due to high neurotransmitter activity in the brain. (Enc. Drug&Alch. Abuse) As cocaine is used, it affects many parts of the brain directly and indirectly. The highs produced by cocaine are actually irregular levels of brain-made neurotransmitters caused by cocaine, not cocaine itself.

The addiction is a strong physiological dependence brought about by low levels of seretonin in the brain. The abuse of cocaine is wide-spread and is expensive financially as well as physically After all of the facts presented, the question that remains to be answered about cocaine abuse is not how, but why..