Torbati D
Brain Res. 1985 Jun 17;336(2):350-3. doi: 10.1016/0006-8993(85)90666-3.
Hyperbaric oxygenation (HBO) at different pressures and durations of exposure produces an increase in regional cerebral metabolic rate for glucose (rCMRgl) in conscious rats. Pentobarbital anesthesia is known to significantly reduce rCMRgl in rats during air breathing. To test if pentobarbital anesthesia is also effective in reducing HBO-induced increases in rCMRgl, the combined effect of pentobarbital anesthesia and HBO on rCMRgl was autoradiographically measured in 28 neuroanatomical structures. Two groups of rats (11 each) were chronically cannulated in one femoral artery and vein 3 days prior to the experiments. Thirty minutes before the rCMRgl measurements the rats were anesthetized with intravenous injection of 50 mg/kg pentobarbital and exposed to either 1-h air breathing at atmospheric pressure or oxygen at 2 atm absolute. No differences in rCMRgl between oxygen-exposed and air-exposed anesthetized rats were observed in 27 of the 28 neuroanatomical structures examined. The superior olivary nucleus was the only one of the 28 structures showing a significant reduction in rCMRgl following anesthesia and HBO. The possible factors involved in the elimination by anesthesia of the previously observed increases in rCMRgl in conscious rats exposed to HBO are discussed.
在清醒大鼠中，不同压力和暴露时长的高压氧疗（HBO）会使局部脑葡萄糖代谢率（rCMRgl）升高。已知戊巴比妥麻醉能显著降低大鼠在空气呼吸时的rCMRgl。为了测试戊巴比妥麻醉是否也能有效降低HBO诱导的rCMRgl升高，通过放射自显影法测量了戊巴比妥麻醉和HBO对28个神经解剖结构rCMRgl的联合影响。两组大鼠（每组11只）在实验前3天经股动脉和静脉进行长期插管。在测量rCMRgl前30分钟，大鼠通过静脉注射50mg/kg戊巴比妥进行麻醉，然后分别在常压下呼吸空气1小时或在2个绝对大气压下呼吸氧气。在检查的28个神经解剖结构中的27个结构中，未观察到暴露于氧气和空气的麻醉大鼠之间rCMRgl存在差异。上橄榄核是28个结构中唯一一个在麻醉和HBO后rCMRgl显著降低的结构。文中讨论了麻醉消除先前观察到的清醒大鼠暴露于HBO时rCMRgl升高可能涉及的因素。
