Fig. 5. The inhibitory effects of local anesthetics on carbachol-induced protein tyrosine phosphorylation in PC12 cells. The cells were treated in the presence (+) or the absence (−) of 5 × 10−4M procaine (Pro), tetracaine (Tetra), lidocaine (Lido), or bupivacaine (Bupi) for 10 min and then stimulated with 1 mM carbachol for 2 min. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis and Western blot analysis with anti-phosphotyrosine antibody were performed. The carbachol-induced protein tyrosine phosphorylation of 44- and 42-kd proteins was inhibited by the presence of each local anesthetic. The molecular mass markers of p44 and p42, expressed in kilodaltons, are indicated on the left with arrows.
