To explore the sensitization variance of acupoint when internal organs is under pathological condition; to observe quantity effect variance of dorsal column nuclei (DCN) to electro acupuncture under both physiological and pathological condition; to explain the central mechanism of acupoint sensitization. Methods: A total of 23 adult male SD rats were used in this study. Visceral nociceptive stimulus was generated by colorectal distension (CRD) and DCN Neuron activity was recorded. The quantity effect variance of neuron activity to electro acupuncture at “Zusanli Shangjuxu” area both before and after CRD was observed. Results: Visceral nociceptive afferents could enhance neuron activity at DCN Neuron to acupoint acupuncture. DCN neuron activity caused by electro acupuncture increased when visceral nociception rose.Conclusion:The area of acupoint could be changed with visceral function. When the visceral function was damaged, the number of response points, area of acupoint receptive filed and sensitivity of acupoint would also change correspondingly.