Dissociated behavior of low-frequency responses and high-frequency oscillations after systemic morphine administration in conscious rats.
It has been proposed that high-frequency oscillations (HFOs) and underlying conventional somatosensory-evoked potentials (SEPs) have different brain origins. To further explore the neural mechanism of HFOs, we recorded the SEPs responding to high-intensity electrical stimulation applied to the hind paw of conscious, freely moving rats. We also investigated the effect of systemic morphine on HFOs and the conventional SEPs. HFOs after high-intensity electrical stimulation showed a widespread distribution in frontal and temporal regions of the brain. The amplitude of HFOs was significantly decreased by systemic morphine, whereas the primary conventional SEP components remained unaffected. The different changes in HFOs and primary SEP components after systemic morphine administration provided further evidence for the hypothesis that HFOs and underlying conventional SEP components have different origins.
Li
Guo-Liang
GL
Department of Anesthesiology, Fourth Affiliated Hospital of Hebei Medical University, Shijiazhuang, China.
Qiao
Zhi-Mei
ZM
Han
Ji-Sheng
JS
Luo
Fei
F
D000818:Animals; D055592:Biophysical Phenomena / Q000187:drug effects* / Q000502:physiology; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000187:drug effects* / Q000502:physiology; D003243:Consciousness / Q000502:physiology; D004558:Electric Stimulation / Q000009:adverse effects / Q000379:methods; D004569:Electroencephalography; D005073:Evoked Potentials, Somatosensory / Q000187:drug effects* / Q000502:physiology; D008297:Male; D009020:Morphine / Q000008:administration & dosage / Q000494:pharmacology*; D009294:Narcotics / Q000008:administration & dosage / Q000494:pharmacology*; D017288:Pain Threshold / Q000187:drug effects / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology
D009294:Narcotics; D009020:Morphine