Sunday, March 21, 2010

3/21/2010

Recently, I’ve seen a lot of television ads for Aricept, so I thought the Alzheimer’s drugs would be a good topic to write about. Neurons communicate with one another by sending impulses across synapses and the synapses do this with chemicals (that are called neurotransmitters). There are a variety of neurotransmitters in different regions of the brain, one of them being acetylcholine, which is used the hippocampus (a region important in memory storage and retrieval).

Acetylcholine is destroyed by the enzyme cholinesterase. Aricept works by blocking the action of cholinesterase (thus is called a cholinesterase inhibitor). In doing so, it raises brain levels of acetylcholine. The idea is that increasing brain levels of this crucial neurotransmitter will benefit memory and behavior. But because the underlying cause for the loss of neurons continues, the effect of a drug like Aricept only postpones the worsening by about 6 to 12 months. These drugs do not reverse the eventual course of the disease.

Other anti-alzheimer drugs are Exelon and Razadyne. Because of varying side effects and possible interactions with other medications, doctors may try different cholinesterase inhibitors until the most effective one is found for the individual. Namenda regulates glutamate, another neurotransmitter which plays a key role in processing information.

When you take a pill it is adsorbed from your gut and then goes everywhere in the body rather than exclusively to the target, like the brain. Acetylcholine is necessary not only for some brain regions, but also in various nerves that control the heart, gut, bladder, and a variety of other function. This is why the undesirable side-effects of anticholinesterase inhibitors are so wide spread.

1 comment:

  1. Hey Allen, a little off subject here but here goes. We're all afraid of Alzheimer's for sure. I'm over 60 and think about it all the time. My question is regarding the younger generation. They are constantly communicating, texting, calling, on the computer etc. They are the kings and queens of multitasking. I saw a program on television that addressed this new generation. One student said he had great difficulty writing one long paper. He could write great short chapters, but tying it all together was very difficult. He was basically thinking in spurts. Keep in mind, as he was writing this paper, he was also texting to friends! Another friend finds texting much easier than actually talking to people. And texting and driving. The worst part of this scenario is people actually think they are doing this well! This may be a very theoretical question, but how do you see this technological age affecting young people? Are we creating a generation of people that have a difficult time doing one thing at a time? Can the brain really multitask all that well?
    Thanks for your input......

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