GJA1 and glaucoma: For example, the Cx43 network can provide neuroprotection during metabolic stress by redistributing resources, regulating extracellular concentrations of glutamate and K+, and preventing hyperexcitable or damaged neurons from inducing abnormal excitability in neighboring cells.[12, 53] However, as glaucoma progresses, particularly in the later stages, the role of Cx43 may shift toward promoting neuronal damage.