Friday, October 20, 2006

Electrochemistry of the Neuron

Best book/blog in the neurosphere:

Also, I have been trying to get a handle on the electrochemistry of the neuron, and to that end have been studying the nearest-known system in physics, since physicists try to understand things and biologists are content to just use whatever instruments the chemists and physicists make. And what is this nearest-neighbor? The P-N semiconductor of course, that eponymous minimal substrate for the most common metaphor in neuroscience, "the brain is a computer". And it turns out there is some weird sh*t going down. Positive charges are just the spaces created by the removal of negative charges, but they can be modeled as if they have a physical extension, can move, and have mass. There is a 'band-gap' (in "potential-space") that separates the electron-filled quantal energy levels and the unfilled, and the size of this gap and its relation to the place-below-which-half-the-energy-levels-are-filled (AKA Fermi Level) determines whether the material is a Conductor, a Resistor, or, if the Fermi Level falls in the band gap, a P-N semiconductor.

What does this have to do with nerves? Well, I realized I don't understand the whole ion channel thingy. Partial pressures...apparently the charge of the ions doesn't matter, in that an overabundance of Ca+ can't influence the action of, say, K+ or Cl- in anyway. Weird, if you think that every drug we put into the body must have its own partial pressure to. And different parts of the body are under different pressures. You've heard about 'the bends' (thanks, Radiohead) of nitrogen 'coming out of solution'. It seems that these affects most be omnipresent in the body where these pressure differentials crop up (and don't forget the microscale of vesicles literally 'popping' out of terminals in the synapse). My uncle is studying something to do with this and the pressure that tumors build up trying to grow against the luminal matrix of the body.

That isn't directly related to my P-N semiconductor ponderous ponderings, but it gives a flavor of the kind of questions I want to ask but don't know enough about yet to. Meanwhile, I am reading about harvesting monoclonal vs. polyclonal antibodies.

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