Sitagliptin pretreatment ameliorated hypoxia/reoxygenation (H/R)-induced cell death of primary cardiac microvascular endothelial cells (CMECs). Cells were preincubated with 100, 200 nM sitagliptin or DMSO vehicle for 12 h, followed by exposure to hypoxia/reoxygenation (H/R) conditions. A. Cell viability of CMECs was assessed by MTT assay; B. LDH released from the cytoplasm to the medium was assayed (*, P<0.01 vs. vehicle group; #, P<0.01 vs. H/R group; $, P<0.01 vs. H/R+100 nM sitagliptin, n=5-6).