HMGB1 and ischemia: The combination of chemical sympathectomy and electroacupuncture pretreatment inhibited HMGB1 expression immediately after ischemia to a greater extent than did electroacupuncture alone (GS+PC6+IR vs. PC6+IR, p = 0.023; Fig. 4C), and it also provided greater cardiac protection (p < 0.05, Fig. 5A–E).