Reduction of cytochrome-c oxidase copper precedes failing cerebral O2 utilization in fluorocarbon-perfused cats.
Reduction of cytochrome-c oxidase copper precedes failing cerebral O2 utilization in fluorocarbon-perfused cats.
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在氟碳灌注的猫中，细胞色素 C 氧化酶铜的减少先于脑部 O2 利用失败。
DOI：
10.1152/ajpheart.1996.271.2.h579
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
Hanley,DF
中科院分区：
文献类型：
--
作者：
Stingele,R;Wagner,B;Kameneva,MV;Williams,MA;Wilson,DA;Thakor,NV;Traystman,RJ;Hanley,DF
我们确定了低电位铜（CuA）的细胞色素c氧化酶的氧化还原状态的脑组织PO 2（PtiO 2）和全球脑耗氧量（CMRO 2）在体内的关系。在常氧和分级缺氧条件下，使用近红外光谱法监测全氟化碳交换猫的细胞色素c氧化酶铜的氧化还原状态。获得了730 ~ 960 nm的连续光谱，并通过830 nm处的吸收变化评估了铜氧化还原状态的变化。PtiO 2通过植入皮质的O2敏感电极测量，CMRO 2通过采集动脉和上级矢状窦灌注液并通过放射性标记微球测量血流量来确定。由于PtiO 2随着缺氧而降低，细胞色素c氧化酶的CuA逐渐减少，而CMRO 2在缺氧的初始阶段没有变化。只有在重度缺氧时，CMRO 2和体感诱发电位的幅度才降低。我们的结论是，CuA网站的细胞色素C氧化酶参与调节，有助于保持CMRO 2恒定。
We determined the relationship of the low-potential copper (CuA) redox state of cytochrome-c oxidase to the brain tissue PO2 (PtiO2) and global cerebral O2 consumption (CMRO2) in vivo. The redox state of cytochrome-c oxidase copper was monitored in perfluorocarbon-exchanged cats under normoxic and graded hypoxic conditions with use of near-infrared spectroscopy. Continuous spectra ranging from 730 to 960 nm were acquired, and the change in copper redox state was assessed by the absorption changes at 830 nm. PtiO2 was measured with O2-sensitive electrodes implanted into the cortex, and CMRO2 was determined by sampling arterial and superior sagittal sinus perfusate and by measuring blood flow with radiolabeled microspheres. As PtiO2 decreased with hypoxia, the CuA of cytochrome-c oxidase became progressively reduced, whereas the CMRO2 was unchanged during the initial stages of hypoxia. Only with severe hypoxia, did CMRO2 and the amplitude of somatosensory evoked potentials decrease. We conclude that the CuA site of cytochrome-c oxidase is involved in a regulatory adjustment that helps maintain CMRO2 constant.