HHcy-stimulated SK and IK expression in SMAs of Tg-hCBS Cbs mice. Mouse SMAs cross-sections were immunostained with antibodies against SK3 (green, A) or IK1 (green, B), and costained with the endothelial marker CD31 (red). Merged image (yellow to orange) shows that SK3 and IK1 are localized in the endothelium and increased in Cbs^−/− mice. (C-D) Immunoblot of SK3 and IK1 in SMA extracts and quantification. Values are means ± SEM (n = 5-7 mice). *P < .05 compared with control mice. CT indicates the control group.