Explain autoregulation of blood pressure and blood flow

Question

Since this is not my area of expertise, I searched Google under the key words "autoregulation blood" to get these possible sources:

http://www.cvphysiology.com/Blood%20Flow/BF004.htm
http://depts.washington.edu/uwtcdlab/autoreg.html
http://www.eurekalert.org/pub_releases/2006-06/mc-bpv062706.php
http://66.102.7.104/search?q=cache:yWOzTmZOY2kJ:www.nil.wustl.edu/labs/raichle/MER_papers/17_The%2520Role%2520of%2520the%2520Peripheral%2520Sympathetic%2520Nervous%2520System%2520in%2520Cerebral%2520Blood%2520Flow%2520Autoregulation.pdf+autoregulation+blood&hl=en&gl=us&ct=clnk&cd=11&client=safari

I hope this helps. Thanks for asking.