Figure 6.

DAPA-mediated microvascular protection is partly compromised in SERCA2^EKO mice. Tie2^Cre transgenic mice and SERCA2^f/f mice were extensively backcrossed on C57B6/J mice for at least nine generations before interbreeding to generate the endothelial specific SERCA2 knockout mice (SERCA2^EKO). The SERCA2^f/f mice were used as the control group. Mice were subjected to 45-min ischemia followed by 2-h reperfusion to induce cardiac ischemia/reperfusion injury (IRI). Dapagliflozin (DAPA, 40 mg/kg/day) was administrated daily via intraperitoneal injection during seven days before IRI surgery. (A) Electron microscopy was used to detect ultrastructural alterations in the cardiac microcirculation. (B) H&E staining was used to observe the morphology of erythrocytes in the cardiac microvasculature. (C, D) Immunohistochemistry was performed to detect the expression of ICAM1 on the surface of cardiac microvessels. (E-G) The expression of IL-6, MCP1, and TNFα mRNA was determined by qPCR. β-actin was used as internal reference. (H-I) TUNEL staining was performed to assess and quantify apoptosis of cardiac microvascular ECs after IRI. Experiments were repeated at least three times and the data are shown as mean ± SEM. Ten animals were used in each group and the dotes in each panel represent the average data of three replicates in each animal. *p < 0.05.