Main | April 2006 »

July 23, 2005

Neurotransmitters and becoming a quitter.

The human body is makes a neurotransmitter called adenosine. Adenosine is the A in ATP that you may remember from your high school biology class. Your body uses the Krebs cycle to make between 36-38 molecules of ATP. It then uses ATP to fuel other activities in the cell. However, adenosine on its own, in the brain attaches to cells and causes them to slow down. Adenosine is the chemical that tells us we’re sleepy. While awake, the levels of it in our body rise. When we are asleep, they go down. This is important.

Caffeine looks a little like adenosine. Its at least shaped enough like it that it can attach to adenosine receptors on cells. You can guess where I’m going with this. Instead of telling cells to slow down and take a breather, caffeine attaches to cells and screams, “GO! FOR THE LOVE OF PETE, GO!” All this going is perceived by the pituitary gland as an emergency. Why else would you need to go so fast? The pituitary gland sets into motion the release epinephrin, which does a number of things in the human body. It slows blood flow to the stomach and the skin. It opens up breathing passages and increases blood flow to muscles. It dilates pupils and prods the liver into releasing sugar into the blood stream. (Sugar, in the form of glucose that your cells then take in and run the Krebs cycle on.) But that’s not the fun part.

Caffeine also manipulates dopamine levels. Dopamine is the feel good chemical, operating in the pleasure centers of the brain. According to the article I read this morning on, caffeine does this dopamine trick via the same pathways as heroin and cocaine, its just more subtle about it. This might explain why caffeine is the drug of choice in public and in polite company. Its certainly my recreational drug of choice.

Or at least it was until six days ago. The half life of caffeine in the human body is about six hours. So, the cup of coffee that I have at three in the afternoon banks about 375 or so milligrams of caffeine. Combine that with 40 mg from the tea I had with breakfast and the fact that I’ve probably had some chocolate for at least another 10 and then maybe some more coffee on break if I’m closing and we’re talking upwards of 600 milligrams a day. (375+375+40+10= 800. Just 200 shy of a full gram!) At least 175 of which is still raising around my body screaming Go! At my cells at midnight. And I wonder why I have trouble sleeping sometimes.

The withdraw process hasn’t been nearly as painful as I thought it would be. I’ve come to the conclusion that I’m better off without it. My way of cutting caffeine has been no coffee or soda. I miss coffee. I miss it SO MUCH. I may have a cup of decaf (internal shudder) today. What is the name of the coffee shop in The Basic Eight Death before Decaf? Bah. I hate being a grown up and having to think about the consequences of things like my addictions.

This was originally published on my original blog The Experiment Continues at