Fig. 2. Various mechanisms that might underlie involvement of VGSCs in galvanotaxis. Contraction could be driven by Ca²⁺ originating from a variety of sources secondary to Na⁺ influx through VGSCs. Alternatively, it could be stimulated by protein kinase A (PKA) activated by cAMP, synthesized by adenylate cyclase, stimulated by Na⁺. Direct interaction between the ß subunits of VGSCs and the cytoskeleton is also possible.