Looking at that abstract that I just put up made me realize that I have over immersed myself in all this of late and that a good number of those who need the info won't understand that mess. So let me give the two cent summary and then a link to one of the handiest tools I have ever found.
"Acute stress increases BBB permeability that is dependent on CRH and mast cells."
That's the part that applies to our discussion. CRH is corticotropin-releasing hormone which is what your brain squirts out to start the process of the "fight or flight" response. The rest is not relevant to us so don't stress yourself over it.
Now, the tool is called "1-Click Answers" and is a work of art. You download it, install, and forget all about it. But anytime, anywhere you encounter a word or phrase that's unfamiliar - just "Alt-Click" on it and a dandy little window pops up and gives you the definition. It sure helps with these papers.
http://www.answers.com/main/home_simple.jsp
-Rick