N–methyl–D–aspartate (NMDA) receptor: it is a receptor-ion channel complex. It is blocked by magnesium and is composed of seven subunits. The receptors are widely distributed in the spinal cord and facilitate nociception. The receptors are involved in dorsal horn excitability seen after primary injury (central sensitisation). Phosphorylation of NMDA receptor is crucial for sensitisation. Wind-up of the dorsal horn is reduced by NMDA receptor antagonists.

Α–amino–3–hydroxy–5–methyl–4–isoxozolepropionic acid (AMPA) receptors: consist of five subunits GLUR1–4. The receptors are mostly found in the spinal cord and dorsal neurons. The receptors are associated with injury-induced plasticity and hyperalgesia. Calcium-permeable AMPA receptors are involved with synaptic plasticity, and thus drugs that can affect these receptors can contribute to analgesia.