Kirkeby O J, Kutzsche S, Risöe C, Rise I R
Institute for Surgical Research and(2)Department of Neurosurgery, The National Hospital, Oslo, Norway.
J Clin Neurosci. 2000 Nov;7(6):531-8. doi: 10.1054/jocn.2000.0788.
Intracerebral nitric oxide (NO) concentration was measured to establish the technique and to investigate the response of the NO concentration to CO(2)variations, hypoxia, and reduced cerebral perfusion pressure. An intracerebral nitric oxide sensor was used in 10 pigs. Cerebral microcirculation was measured by laser Doppler flowmetry. Five pigs received 40 mg/kg nitro-1-arginine methyl ester (L-NAME). Baseline NO concentration was 246 +/- 42 nM. Hypercapnia increased cerebral microcirculation (P< 0.05) and NO concentration (P< 0.05). Hypoxia decreased NO concentration (P< 0.05). During high intracranial pressure, cerebral microcirculation decreased (P< 0.05) before the NO concentration decreased (P< 0.05), and after normalisation of the intracranial pressure the NO concentration increased, but more slowly than the cerebral microcirculation. L-NAME caused a decrease in cerebral microcirculation (P< 0.05) and NO concentration (P< 0.05) to a new steady state, and L-NAME attenuated the changes in NO concentration after hypoxia (P< 0.05) and high intracranial pressure (P< 0.05). In conclusion, the electrochemical sensor appears to reliably detect changes in localised intracerebral NO concentration and seems to be a promising tool for direct measurement of this chemically unstable substance.
测量脑内一氧化氮（NO）浓度以建立该技术，并研究NO浓度对二氧化碳变化、缺氧和脑灌注压降低的反应。在10头猪中使用了脑内一氧化氮传感器。通过激光多普勒血流仪测量脑微循环。5头猪接受了40mg/kg硝基-1-精氨酸甲酯（L-NAME）。基线NO浓度为246±42nM。高碳酸血症增加了脑微循环（P<0.05）和NO浓度（P<0.05）。缺氧降低了NO浓度（P<0.05）。在颅内压升高期间，脑微循环在NO浓度降低之前就已下降（P<0.05），而在颅内压恢复正常后，NO浓度升高，但比脑微循环升高得慢。L-NAME导致脑微循环（P<0.05）和NO浓度（P<0.05）下降至新的稳定状态，并且L-NAME减弱了缺氧（P<0.05）和高颅内压（P<0.05）后NO浓度的变化。总之，电化学传感器似乎能够可靠地检测局部脑内NO浓度的变化，并且似乎是直接测量这种化学性质不稳定物质的一种有前景的工具。
