NHE wrote:Hi 1eye,1eye wrote:Foist of all, I don't understand as I haven't watched enough Gray's Anatomy.
How does reflux weaken the endothelium (or other Latin word to that effect)? Are we talking ballooning here?
I posted this information a few pages back...
http://www.thisisms.com/ftopicp-128100.html#128100Simka's letter in a nutshell... Endothelial cells are the cells that line the blood vessels. In the brain, the endothelial cells make up the blood brain barrier. When blood flows past the endothelial cells, the cells experience shear stress. In response to this stress, the cells upregulate the proteins that make the connections between them stronger, i.e., the statement about tight junctions. Stronger tight junctions help the blood brain barrier limit what can pass between the endothelial cells from the blood to the brain, e.g., the white blood cells of the immune system. Simka's point appeared to be that with reduced blood flow seen in CCSVI in MS patients, the endothelial cells will not experience as much shear stress and will therefore have weaker tight junctions between them leading to increased permeability of the blood brain barrier and that this change in the blood brain barrier may be a contributing factor to the development of MS. In addition, Simka noted that low shear stress upregulates the protein, ICAM-1, that's used by leukocytes to cross the blood brain barrier. This is like a double edged sword against the blood brain barrier, i.e., not only is it more permeable but the adhesion molecules needed by the immune system cells to cross the blood brain barrier are more abundant (that's like opening all the windows in your house just a bit and then putting signs out for the burglars). Simka also proposed that he thought that surgical intervention was a good idea.
It seemed like a relevant response to Sneakycat's post which discussed Tysabri. In effect, if Dr. Simka's statement is correct, then CCSVI is a condition which increases the permeability of the blood brain barrier. An analogy would be that it's building more doors for the immune cells to cross into the brain. Tysabri would then be like a vandal that comes around and superglues all of the locks. It may be better to stop the installation of the doors in the first place rather than to address the increased permeability afterwards (note, that's just my own interpretation).
good back and forth
i like it