CNR1 and peripheral nerve injury: Due to the lack of presynaptic inhibition of CB1 (Balezina et al., 2021; Patzke et al., 2021), peripheral nerve injury leads to glial overactivation and the release of a large amount of pain-causing substances and inflammatory mediators, which eventually causes exaggerated neuropathic pain, and the specific deep-level mechanism needs to be further studied.