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nephron: interstitial space, intercellular space, peritubular capillaries

Discussion in 'MCAT Study Question Q&A' started by puffylover, Apr 18, 2010.

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  1. puffylover

    puffylover

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    can anyone explain the microscopic set up of the nephron. for example, the nephron is made of epithelial cells? what's outside this? interstitial space? and outside this... peritubular capiliaries?

    so for reabsorption the ion would have to go from tubule through epithelial cell to interstitial space to capillary??

    the question that got me thinking about this:

    which of the following conditions will favor the movement of water, ions, and glucose from the intercellular space of the proximal tubule into the peritubular capiliaries?

    A: low capillary hydrostatic and high capillary osmotic pressure
  2. puffylover

    puffylover

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    btw explanation for answer (which got me further confused):

    ...moving fluid and solutes out of capillaries into either the intercellular space (in systemic capillaries {what's this referring to?}) or into the bowman's capsule (in glomerular capillaries)
  3. docelh

    docelh

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    lumen --> epithelial --> basolateral --> interstitial --> capillary endothelium
  4. pdiddy916

    pdiddy916

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    the tubule are made of a single layer of epithelial cells so the molecules must pass through transporters in lumenal side of the epithelial cells and then pass through basolateral pumps/transporters to enter the interstitial space. They are able to enter the capillary due to the low hydrostatic pressure and high osmotic pressure of the capillaries.

    This makes sense because the low hydrostatic pressure in the capillaries means that the blood presssure is not high which would push molecules out and since the osmotic pressure is high this allows for water and glucose to enter.

    There is an equation that you use to calculate specifically if absorption of filtration would occur using hydrostatic and osmotic pressure but knowing the low hydrostatic and high osmotic results in absorption and that high hydrostatic and low osmotic results in filtration is sufficient.

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