Figure 2.

Involvement of Ca²⁺ ions, Ca²⁺ channels, and Ca²⁺-dependent proteins in death or survival of remote glial cells (RGC) in crayfish stretch receptors after axotomy (AT), based on our experimental data. AT induces Ca²⁺ influx into axolemma and the elevation of Ca²⁺ levels in cytosol of neuron and glia ([Ca²⁺]_i), promoting the cessation of neuron firing and glial death. The work of SERCA, pumping Ca²⁺ from cytosol, protects remote glial cell from necrosis and apoptosis. Protein kinase C (PKC) and calmodulin kinase II (CaMKII) are involved in the necrosis of RGC, but PKC decreases their apoptosis, as well as Ca²⁺-dependent potassium channels K(Ca). Extracellular Ca²⁺ ([Ca²⁺]_o), promotes apoptosis, but decreases the necrosis of RGC. Sharp arrowheads: increase effects. Blunt arrowheads: decrease effects. Dashed lines: the effect takes place only after AT. Red: detrimental effects. Blue: protective effects.