The unit discharges in the dorsomedial nucleus of the hypothalamus (DMH) were extracellularly recorded with microelectrodes in trauma models of male Sprague-Dawley rats. The main results were as follows : (1) The tota...The unit discharges in the dorsomedial nucleus of the hypothalamus (DMH) were extracellularly recorded with microelectrodes in trauma models of male Sprague-Dawley rats. The main results were as follows : (1) The total number of spontaneously discharged units in DMH of trauma rats was markedly decreased while the number of pain-sensitive units (nociceptive neurons) did not change obviously. (2) The electroacupuncture (EA)at Zusanli (ST36) and Sanyinjiao (Sp6) decreased the spontaneous and pain-evoked firing (discharge) rate, and shortened the durations of pain-evoked firing of pain-excited units in DMH. It also resulted in increase in spontaneous discharge rate of pain-inhibited units and relief of their inhibition from the peripheral noxious stimulations. These results suggest that the depression of the function of DMH caused by the persistent peripheral noxious stimulation may be one of the mechanisms of hyperalgesia. EA at the points of Zusanli (ST36) and Sanyinjiao (Sp6) can interfere with the conduction of pain signals to DMH in the central nervous system and thereby prevent DMH from being depressed , which may partly account for the central mechanisms of acupuncture-analgesia in chronic pain state.展开更多
文摘The unit discharges in the dorsomedial nucleus of the hypothalamus (DMH) were extracellularly recorded with microelectrodes in trauma models of male Sprague-Dawley rats. The main results were as follows : (1) The total number of spontaneously discharged units in DMH of trauma rats was markedly decreased while the number of pain-sensitive units (nociceptive neurons) did not change obviously. (2) The electroacupuncture (EA)at Zusanli (ST36) and Sanyinjiao (Sp6) decreased the spontaneous and pain-evoked firing (discharge) rate, and shortened the durations of pain-evoked firing of pain-excited units in DMH. It also resulted in increase in spontaneous discharge rate of pain-inhibited units and relief of their inhibition from the peripheral noxious stimulations. These results suggest that the depression of the function of DMH caused by the persistent peripheral noxious stimulation may be one of the mechanisms of hyperalgesia. EA at the points of Zusanli (ST36) and Sanyinjiao (Sp6) can interfere with the conduction of pain signals to DMH in the central nervous system and thereby prevent DMH from being depressed , which may partly account for the central mechanisms of acupuncture-analgesia in chronic pain state.
