DDIT3 and Hyperglycemia: To confirm the roles of the hyperglycemia-activated ATF6-CHOP signaling in hepatic IRI, we treated hyperglycemic mice with 4-phenylbutyrate (PBA), western blot results indicated that higher levels of cATF6 and CHOP were detected in the 90 min ischemic livers of hyperglycemic mice at 0 and 6 h of reperfusion, whereas PBA effectively inhibited the hyperglycemia-triggered ATF6-CHOP pathway (Fig. 2A).