[Influence of microiontophoretic morphine on nociceptive responses of Pf neurons after lesion of SmI].
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.
Zheng
X
X
Institute of Acupuncture, China Academy of Traditional Chinese Medicine, Beijing.
Chen
Z
Z
Shi
H
H
Xu
W
W
D000818:Animals; D005260:Female; D007478:Iontophoresis; D008297:Male; D009020:Morphine / Q000494:pharmacology*; D009619:Nociceptors / Q000187:drug effects* / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D013003:Somatosensory Cortex / Q000502:physiology; D013787:Thalamic Nuclei / Q000502:physiology*
D009020:Morphine