REN and hypertensive disorder: Preoperativeneuroinflammation may be caused by hypertension’s contribution to a disruptedblood-brain-barrier, the renin-angiotensin-aldosterone-system’s contribution toreactive oxygen species, and pro-inflammatory cytokines (tumor necrosis factoralpha, IL-1beta, IL-6) in the presence of decreased IL-10 mRNA by angiotensinII[32,33].