Evidence of microcirculatory endothelial dysfunction was documented in Complex Regional Pain Syndrome aka RSD. The peripheral changes could help trigger the central sensitization process.
Schattschneider, J MD et al.
Neurology Volume 67(4), 22 August 2006, pp 673-675
They surmise the resultant hypoxia will cause acidosis, and trigger nociceptors which in turn will trigger central sensitization.
Comment – this was the old picture developed for Myofascial Trigger Points until they found cytokines and disturbed muscles factors were at work.