MLCK inhibitor peptide 18

This cell-permeable small molecule is a potent and selective competitive inhibitor of myosin light chain kinase (MLCK), exhibiting an IC50 of 50 nM. It shows >4000-fold selectivity over CaM kinase II and no activity against PKA, making it a valuable tool for investigating smooth muscle contraction, endothelial barrier function, and cell motility in both cellular and animal models.