Johny's Brain on Coke

	 Johny's Brain on Coke
The following is a hypothetical and extremely unrealistic dialogue between my hypothetical friend Johnny and me. The conversation takes place at a Wesleyan party and concerns Johnny?s decision to snort cocaine. The reason I chose cocaine for the topic of this dialogue is because of its widespread prevalence on campus, as well as the fact that several friends of mine frequently do coke for recreational purposes.Me. Hey Johnny, what you up to?

Johnny. Nothing much dude, just doin? some lines. You in?

Me. No Johnny, I think I?ll have to pass.

Johnny. What?s the problem, you broke?

Me. Well actually I?ve been taking this class called biopsych where I?m learning all this cool stuff about drugs and what they do to your brain, and?

Johnny. `Cause I mean I can spot you some cash if you?re low on bills.

Me. Dude, are you even listening to what I?m saying?

Johnny. What? Oh my bad. What did you say you learned?

Me. Well for one thing I learned exactly how coke works in your brain.

Johnny. Really? That sounds like something I should probably know about, but I really don?t know like nothing about biology and stuff.

Me. That?s ok, I?d be happy to explain it to you. Ok I?ll start from the basics. I?m sure you know that all electrical signals in your brain and body are carried via cells called neurons.

Johnny. Uh, right.

Me. Well the way this electrical impulse travels down the neuron is by rapidly depolarizing the cell?s membrane, opening ion channels in it. When the impulse, also known as the action potential, reaches the end of the neuron, (the axon terminal), it triggers in influx of calcium ions into the presynaptic membrane.

Johnny. Presynaptic?

Me. Ok I?m going too fast?a synapse is the site at which two different neurons meet. It is here that the electrical impulse is or is not transmitted to the next neuron via chemical messengers called neurotransmitters.

Johnny. Oh, I?ve heard of those!

Me. Good for you Johnny, good for you. As I was saying, when the calcium ions flood in, they cause these little sacs called vesicles which are filled with neurotransmitters to fuse with the membrane and release them into the area between the two neurons, called the synaptic cleft. The neurotransmitters then bind to receptors on the postsynaptic membrane of the other neuron. Once bound, these receptors, which are also ion channels, will open, allowing the inward flow of ions, which has the ability to create once again an action potential that will continue down the next neuron.

Johnny. That?s great, I?m not sure I got all of it, but thanks for your enthusiasm?What does this have to do with coke again?

Me. I?m getting there Johnny my boy, patience is a virtue. You see, what cocaine does is it messes with your neurotransmitters. Do you know what an agonist or an antagonist is Johnny?

Johnny. Um, antagonists are in books and stuff?

Me. ?wow. Ok let me explain. Agonists are chemicals that enter the brain which have the ability to act like a neurotransmitter and bind to the receptors, triggering them. Antagonists are chemicals that prevent neurotransmitters from binding to receptors, so the receptors are not triggered.

Johnny. So is coke an agonist or an antagonist.

Me. That?s a very good question Johnny. Technically cocaine is an agonist, because it binds to receptors like a neurotransmitter would and increases the amount of neurotransmitter in the synaptic cleft. It does this by blocking the receptor channels that would try to reabsorb the left over neurotransmitter back into the presynaptic membrane. For this reason we can say that cocaine acts presynaptically. If it dealt with receptors on the postsynaptic membrane of the other neuron, it would be said to act postsynaptically.

Johnny. But why does doing this to my neurotransmitters make me feel so good?

Me. With more neurotransmitters than usual staying there for longer than usual in the synaptic cleft, your neurons fire harder and longer, making you feel alert and energized. Amphetamines, as you probably know, provide effects similar to those of coke. This is because they are also presynaptic agonists that block reuptake of neurotransmitters.

Johnny. Wait, I thought we have a bunch of different kinds of neurotransmitters. Does coke affect all of them?

Me. Once again, a very good question. Cocaine blocks monoamine transporters, so only neurotransmitters belonging to the monoamine group are affected. These include norepinephrine, adrenaline, dopamine, and serotonin. Norepinephrine is affected the most. The result is a stimulating effect which from the looks of things, I don?t need to explain.

Johnny. Oh I know all about the effects, let me tell you. I feel euphoric, energized, motivated, important, and for some reason I?m not hungry anymore.

Me. Ya know Johnny, I know you feel great now, but another thing I learned in my biopsych class was that cocaine has some pretty nasty withdrawal symptoms, especially if you start taking it a lot and become addicted.

Johnny. Interesting?go on.

Me. After your high is over you will start to come down. Your euphoria will most likely be replaced by depression. You?ll become seriously tired from all the physical and mental activity you?re experiencing. You?ll also find yourself extremely hungry, as your body will crave nourishment to make up for all that activity.

Johnny. Wow, this is certainly good to know. I mean recently I?ve been doing coke like every other day, but after hearing this I think I might have to cut back. Just what is it that makes people like me start abusing drugs, I wonder?

Me. Well Johnny, there are lots of reasons that people abuse drugs. Some do it `cause they want to escape the pains of reality. For these people drugs offer a brief alleviation of the depression, anxiety, or banality of their sad lives. Some people abuse drugs simply because they are available and see them as great forms of recreation. Some people?

Johnny. Ok, ok. I get it. Thanks for the info session, it?s been well appreciated. But I gotta take off now?I promised my friend I?d pack a bowl with him tonight and I?m already late. Later dude.

Johny's Brain on Coke 8.1 of 10 on the basis of 2560 Review.