Nerve injury decreases pain perception nerve fibers.For example, the decrease or lack of P2X3 positive nerve fibers will induce hypoalgesia[9].

• 损伤可减少疼痛感受神经纤维的数量，如P2X3-受体阳性神经纤维减少或缺乏时可诱导痛觉减退[9]。