TNF and peripheral nerve injury: Besides the neuronal expression of TNFR1 and IL‐1R, they are expressed in astrocytes and microglia and contribute to glial activation.[25, 37, 41] TNF‐α and IL‐1β induce glia‐mediated synaptic long‐term potentiation in the spinal cord lamina I neurons and thermal hyperalgesia.[37] Thus, NFAT1‐mediated TNF‐α and IL‐1β upregulation facilitates synaptic transmission and glial activation/proliferation after peripheral nerve injury.