Figure 1. Endothelial Kir2.1 regulates FIV.

A. Tamoxifen-induced eGFP expression in Cdh5.Cre^ERT2ROSA^mT/mG mouse mesenteric arteries, en face (scale bar=100 μm). B. Expression of Kir2.1 mRNA in freshly isolated mesenteric ECs from Cdh5.Cre^ERT2Kir2.1^fl/fl mice injected with tamoxifen or vehicle (n=4 pairs, *p<0.05). C. (Upper) Representative traces of Kir2.1 currents in freshly isolated mesenteric ECs from Cdh5.Cre^ERT2Kir2.1^fl/fl mice injected with tamoxifen or vehicle. (Bottom) Average of Kir 2.1 current densities with tamoxifen (n=9,10.1±2.7 pF) or vehicle (n=9, 16.1±1.4 pF, ***p<0.01). D. (Left) Representative traces of FIV in mesenteric arteries from Cdh5.Cre^ERT2Kir2.1^fl/fl with tamoxifen and vehicle injection, compared to Cdh5.Cre^ERT2ROSA^mT/mG injected with tamoxifen. (Middle) FIV in mesenteric arteries (n=8 pairs for tamoxifen and vehicle, n=6 for Cre control, *p<0.05). (Right) Comparison of FIV at Δ100 cmH₂O from ii (*p<0.05). E. (Left) Representative traces of FIV in mesenteric arteries from male and female Cdh5.Cre^ERT2Kir2.1^fl/fl mice with tamoxifen or vehicle. (Middle) FIV of mesenteric arteries from male and female mice (n=4 groups). (Right) Comparison of FIV at Δ100 cmH₂O from the middle (n=4 groups). F. (Left) Representative traces of FIV in mesenteric arteries from Cdh5.Cre^ERT2Kir2.1^fl/fl with tamoxifen or vehicle with Cdh5-WTKir2.1 or empty adenoviral constructs. (Middle) FIV of mesenteric arteries (n=8 pairs, *p<0.05). (Right) Comparison of FIV at Δ100 cmH₂O from the middle (*p<0.05). (Pap: Papaverine, used to confirm no deterioration of the vascular smooth muscle dependent vasodilation.)