Evidence of microcirculatory endothelial dysfunction was documented in Complex Regional Pain Syndrome aka RSD. The peripheral changes could help trigger the central sensitization process.
Endothelial dysfunction in cold type complex regional pain syndrome
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.