(A) A significant increase in mRNA levels of CD44 was observed in the retinas of diabetic animals (**p<0.01, n=6–7). However, retinal protein expression of CD44 was decreased (***p<0.001, n=5) in diabetic rats compared to non-diabetic rats (B). As compared to normal glucose, RRMEC treated with high glucose had a significant increase in both (D) mRNA (*p<0.05, n=6) and (E) protein levels (*p<0.05, n=6) of CD44. In addition, the (C) plasma (n=6) and (F) media levels of CD44 (n=6) were significantly higher (p<0.05) under hyperglycemic conditions, suggesting increased shedding of CD44 in diabetes.