Zheng X, Chen Z, Shi H, Xu W
Institute of Acupuncture, China Academy of Traditional Chinese Medicine, Beijing.
Zhen Ci Yan Jiu. 1995;20(3):18-21.
Neuronal responses in thalamic nucleus parafasciculus (Pf) to microiontophoretic morphine were examined in 20 wistar rats after lesion of SmI. Extracellular recordings were made with five-barreled glass microelectrodes. The results showed that the spontaneous responses of Pf neurons were not statistically changed (n = 11, P > 0.05), but their nociceptive responses were attenuated at 0-8 minutes after iontophoretic morphine (n = 11, P < 0.05). There were statistically significant differences in nociceptive responses between morphine and saline groups at 0-8 minutes after iontophoresis. The results suggest that morphine may be involved in corticofugal modulation of nociceptive responses in thalamic Pf neurons.
