How is an eyeball like an erection?


My next lecture in my neurobiology course is going to be about metabotropic receptors and how modulating internal cGMP levels is one way neuronal activity can be affected. I was planning to use the eye as an example of this process — but now Revere has inspired me to add a bit about the penis and viagra to the lecture. Here at UMM, we’re all about giving students information they can use.

Comments

  1. Moses says

    I think that this link to footage from the U.S. Congress explains exactly how an eyeball is like an erection.

    Nothing better to do that worry about that? No wonder our country is headed down the shitter.

  2. RamblinDude says

    Cuttlefish: Evidently the spam filter wants no connection between the eyeball and “erection”.

  3. Torbjörn Larsson, OM says

    Cuttlefish, ScienceBlogs spam blocker is really shy about scientific biological traits such as erections.

    Btw, I wonder why they think loosing sight and hearing is rare when sporting an erection? Better not remind them that added to this…, um, display of concentration, and orgasm “shuts down” the frontal cortex.

  4. Torbjörn Larsson, OM says

    Cuttlefish, ScienceBlogs spam blocker is really shy about scientific biological traits such as erections.

    Btw, I wonder why they think loosing sight and hearing is rare when sporting an erection? Better not remind them that added to this…, um, display of concentration, and orgasm “shuts down” the frontal cortex.

  5. Torbjörn Larsson, OM says

    “display of concentration, and orgasm” – display of concentration, an orgasm

  6. Torbjörn Larsson, OM says

    “display of concentration, and orgasm” – display of concentration, an orgasm

  7. Mike from Ottawa says

    “Revere has inspired me to add a bit about the penis and v*agra to the lecture. Here at UMM, we’re all about giving students information they can use.”

    If the utility you see for your students is in the v*agra aspect, then I think you’ve not done UMM marketing any good: “UMM: Putting the ‘ED’ in ‘.edu’!”

  8. Mike from Ottawa says

    Apparently Scienceblogs doesn’t like posts that contain the word “v!agra” in them. I couldn’t post the above until I substituted those asterisks, or, as in this one, an exclamation mark.

  9. says

    Hmm…with apologies, then… and please, PZ, delete it if you wish…

    At one time or other, each sister and brother
    Has pondered the musical question
    (The topic’s not easy, just take it from PZ):
    How an eyeball is like an er*ction.

    The answers may vary–be skeptically wary–
    Like “Both can display your affection.”
    Well, so can a rose, but that doesn’t disclose
    How an eyeball is like an er*ction.

    Perhaps evolution provides a solution
    Both organs arise through selection
    But so, then, do fingers; the question still lingers
    How an eyeball is like an er*ction.

    We may hope to deduce, if we try to reduce
    To a chemical sort of connection
    But will “similar stuff” prove an answer enough
    How an eyeball is like an er*ction?

    Nitric Oxide (you know, you can call it NO)
    Causes GuMP to take up a collection
    So that GuMP, for a lark, keeps your dick “in the dark”
    Thus an eyeball is like an er*ction

    Reproductive success got us into this mess
    So it might get us out, on reflection–
    But V!agra, we find, is not blindly designed
    We distinguish both eye and er*ction.

    With both vision and hearing, the answers are nearing
    (Although we can’t hope for perfection),
    And for now it’s just fine as a bad pick-up line:
    How an eyeball is like an er*ction.*

    (*answer: “It’s an empirical question–let’s experiment, and find out.)

  10. truth machine says

    Nothing better to do that worry about that? No wonder our country is headed down the shitter.

    Um …

  11. says

    If you are going to talk about sGC and NO, you have to mention this, one of the most important recent results in NO physiology.

    http://www.pnas.org/cgi/content/full/101/1/37

    What it does is couple NO and ATP physiology. That lets NO (which is freely diffusible into all tissue compartments) regulate ATP levels in those different tissue compartments so they can go up and down in sync. That lets adjacent cells (as for example in a muscle) have the same ATP level and so the same rate of work production.

    If you are going to talk about Sildenafil, you should mention this,

    http://archinte.ama-assn.org/cgi/content/full/166/16/1763

    that by blocking PDE5, the feedback of the NO regulatory system is affected, and (no doubt) physiological pathways not involving cGMP don’t work as well, such as the regulation of breathing via RSNOs

    http://www.nature.com/nature/journal/v413/n6852/full/413171a0.html

    This relates to my research on basal levels of NO, where because all NO sensors only sense the sum of NO from all sources, a change in the basal level affects all NO mediated pathways with no threshold. That is because NO is already in the “active range”, any change in the basal level will affect the output of that feedback regulated pathway.