Araki R, Nashimoto I, Takano T
Department of Hygiene, Saitama Medical School, Japan.
Adv Exp Med Biol. 1988;222:375-81. doi: 10.1007/978-1-4615-9510-6_44.
By measuring near-infrared transmittance spectra, we examined the effect of HBO on cerebral Hb oxygenation in normal and ischemic brain in the anesthetized rat. The oxygenation state of Hb was around 80% in the rat brain under 1 ATA air breathing. HBO did not induce further cerebral Hb oxygenation above 2 ATA in control animals but improved tissue oxygenation in the ischemic brains. The oxidation-reduction state of cyt. aa3 in the normal brain was not affected by HBO. In the ischemic brain, however, HBO prevented ischemia-induced reduction of cyt. aa3. Non-invasive optical monitoring of COHb with visible reflectance spectrophotometry was also examined. HBO markedly accelerated dissociation of COHb. Tight correlation was found between the optical signal and COHb content determined from blood samples. These results demonstrated the usefulness of optical monitoring in vivo under hyperbaric conditions.
通过测量近红外透射光谱，我们研究了高压氧（HBO）对麻醉大鼠正常脑和缺血脑内血红蛋白（Hb）氧合的影响。在1个绝对大气压（ATA）空气呼吸条件下，大鼠脑内Hb的氧合状态约为80%。在对照动物中，2个ATA以上的HBO并未进一步诱导脑内Hb氧合，但改善了缺血脑的组织氧合。正常脑内细胞色素aa3的氧化还原状态不受HBO影响。然而，在缺血脑中，HBO可防止缺血诱导的细胞色素aa3还原。我们还研究了用可见反射分光光度法对碳氧血红蛋白（COHb）进行无创光学监测。HBO显著加速了COHb的解离。发现光学信号与从血样中测定的COHb含量之间存在紧密相关性。这些结果证明了在高压条件下进行体内光学监测的实用性。
