（Z)-PD151746

PD 151746 is a highly selective calpain inhibitor. Its inhibitory activity against μ-calpain (Ki=0.26±0.03 μM) is approximately 20-fold higher than that against m-calpain (Ki=5.33±0.77 μM).

Methods:
HMEC-1 cells were seeded in 60 mm culture dishes and divided into the blank control group, the 200 μg/ml oxLDL treatment group (20 h), and the 200 nM STS treatment group (4 h). In the oxLDL-induced injury model, cells were co-treated with 20 μM PD 151746 or 50 μM BAF, respectively. Cells from each group were collected for protein extraction. Western blot analysis was performed following electrophoresis and membrane transfer. The PVDF membranes were incubated with a monoclonal antibody against α-fodrin for target protein detection. The absorbance values of the 150 kDa and 120 kDa protein bands were scanned and quantified to calculate the A150/A120 ratio. The experiment was repeated five times, and representative blot Results: were selected for analysis.
Results:
Both oxLDL and STS induced the cleavage and activation of α-fodrin in HMEC-1 cells, resulting in altered expression of the characteristic 150 kDa and 120 kDa bands. Co-treatment with PD 151746 or BAF regulated the oxLDL-induced cleavage level of α-fodrin. The A150/A120 absorbance ratio was used to quantify the degree of protein activation in each group. Repeated experiments showed consistent trends, and the presented blots were representative [2].