Figure 7.
Changes in retinal vascular function. Due to I/R, PKA (protein kinase A) signaling and NADH-cytochrome b5 reductase 3(Cyb5r3) is upregulated as self-protective mechanism to maintain endothelial function and vasodilation, while eNOS signaling is downregulated as an indication of endothelial dysfunction. Administration of H2S activated estrogen receptor signaling to facilitate vascular relaxation. H2S also reduced the abundance of annexin A6, which plays a central role in artery calcification. Combined together, H2S protected the blood flow regulatory mechanisms and enabled a less constricted vascular environment in retina against I/R injury.