(-)-Blebbistatin ((S)-(-)-Blebbistatin) is the S enantiomer of blebbistatin. (-)-Blebbistatin is a potent and selective myosin II inhibitor (IC50=0.5-5 μM). (-)-Blebbistatin can be used to inhibit cardiac myosin, non-muscle myosin II, and skeletal muscle myosin.

Non-muscle myosin II ATPases:0.5 μM-5 μM, Smooth muscle myosin:80 μM, non muscle myosin II ATPase (cell-free assays):2 μM

方法：小鼠肝星状细胞 HSCs 用 (-)-Blebbistatin (12.5-50 µM) 处理 2 h，使用 microscopy 观察细胞形态。
结果：当用 (-)-Blebbistatin 处理 2 h，细胞变得更小，获得更多的树突形态，并且具有更少的应力纤维和片状足。[1]
方法：猪 TM 细胞用 (-)-Blebbistatin (25-100 µM) 处理 2 h，使用 Western Blot 检测靶点蛋白表达水平。
结果：对照样品和药物处理样品之间的 MLC 磷酸化状态没有差异。[2]

方法：为研究对动脉血栓形成的作用，将 (-)-Blebbistatin (1 mg/kg) 腹腔注射给 C57BL/6J 小鼠，30 min 后用 FeCl3 构建颈动脉血栓形成模型。
结果：(-)-Blebbistatin 通过小鼠动脉血管组织中的 GSK3β-NF-κB 信号通路，显著减少 FeCl3 溶液诱导的小鼠颈动脉血栓形成，抑制 NMMHC IIA 的表达并阻碍 TF 的表达。[3]

Inhibition of Cox Activity: Inhibition of Cox-1 activity is measured by monitoring oxygen consumption during the conversion of arachidonic acid to PGs using a Clark-type O2-electrode. The reaction mixture contains ～0.2 units Cox-1 in 100 μL of microsome fraction derived from ram seminal vesicles as a crude source of Cox-1 (specific activity 0.2–1 units/mg protein) or 0.23 units of recombinant human Cox-2 (specific activity 43 units/mg protein). For calculation, the rate of O2 consumption is compared with a DMSO control (100% activity). Piroxicam, a nonsteroidal anti-inflammatory drug, is used as positive inhibitory substance for Cox-1 activity with an IC50 of 0.35 ± 0.05 μM (n = 2). Alternatively, nimesulide, a Cox-2 specific inhibitor, inhibits Cox-2 activity by 52 ± 5.7% (n = 2) at a concentration of 50 μM.

Freshly isolated HSCs are replated on 96-well plate. At day 3, medium is replaced by serum-free medium and cells are starved overnight, treated with or without blebbistatin (25 μM) for 2 h followed by stimulation with platelet-derived growth factor-BB (20 ng/mL). After an overnight incubation, the WST-1 cell proliferation assay are performed[3].