Epigenetic down-regulation of BK channel by miR-181a contributes to the fetal and neonatal nicotine-mediated exaggerated coronary vascular tone in adult life.

•Perinatal nicotine induces fetal programming of adult coronary heart dysfunction.•Perinatal nicotine selectively increases miR-181a in coronary arteries in offspring.•The enhanced miR-181a epigenetically represses BKCa β1 gene and channel function.•The decreased BKCa channel leads to development of coronary dysfunctional phenotype.•BKCa targeting miR-181a may be a novel therapeutic target for heart ischemic diseases associated with fetal stress exposure.