Riddle et al. (25) reported that components of the UPR (heat shock protein a5 [Hspa5], ATF6, and p-eIF2) were increased in the retroperitoneal adipose tissues of 3-week-old (3 W) IUGR rats induced by ligation, which contributed to the development of glucose intolerance in male IUGR rats. This evidence concerns the gene ATF6 and fetal growth restriction.