Nagasaka H, Hayashi K, Genda T, Miyazaki T, Matsumoto N, Matsumoto I, Hori T, Sato I
Department of Anesthesiology, Saitama Medical School.
Masui. 1994 Jul;43(7):1015-9.
The effects of isoflurane (0.5% and 1.5%) on the spinal dorsal horn wide dynamic range (WDR) neuronal activity were studied in either spinal cord intact or spinal cord-transected cats. Extracellular activity was recorded in the dorsal horn from single WDR neurons responding to noxious and non-noxious stimuli applied to the cutaneous receptive fields on the left hind foot pads of intact or decerebrate, spinal cord transected (L1-2) cats. When bradykinin (BK) 10 micrograms was injected into the femoral artery ipsilateral to the recording site as the noxious test stimulus in the spinal cat, all of 17 WDR neurons gave excitatory responses which were not depressed by 0.5% isoflurane but were depressed significantly by 1.5%. On the other hand, when the injection of BK 10 micrograms into the femoral artery ipsilateral to the recording site was used in the intact cat, 13 of 24 WDR neurons (54%) gave excitatory responses, which were significantly depressed by 0.5% and 1.5% isoflurane, and 11 of 24 WDR neurons (46%) gave inhibitory responses, which were significantly depressed by 0.5% and 1.5% isoflurane. We have found that isoflurane reduces the excitation as well as the inhibition of dorsal horn WDR neuronal activity induced by BK injection.
在脊髓完整或脊髓横断的猫中，研究了异氟烷（0.5%和1.5%）对脊髓背角广动力范围（WDR）神经元活动的影响。在完整或去大脑、脊髓横断（L1-2）的猫的左后脚垫皮肤感受野施加有害和无害刺激时，记录单个WDR神经元在背角的细胞外活动。当将10微克缓激肽（BK）注入记录部位同侧的股动脉作为脊髓猫的有害测试刺激时，17个WDR神经元全部产生兴奋反应，这些反应不受0.5%异氟烷抑制，但受到1.5%异氟烷的显著抑制。另一方面，当在完整猫中使用将10微克BK注入记录部位同侧股动脉时，24个WDR神经元中有13个（54%）产生兴奋反应，这些反应受到0.5%和1.5%异氟烷的显著抑制，24个WDR神经元中有11个（46%）产生抑制反应，这些反应也受到0.5%和1.5%异氟烷的显著抑制。我们发现，异氟烷可降低BK注射诱导的背角WDR神经元活动的兴奋和抑制。
