Reid J M, Paterson D J, Ashcroft F M, Bergel D H
University Laboratory of Physiology, University of Oxford, UK.
Pflugers Arch. 1993 Nov;425(3-4):362-4. doi: 10.1007/BF00374187.
The increase in blood flow in the cerebral cortex of the anaesthetized rat during hypoxia and hypercapnia was investigated. Cerebral blood flow (CBF) was measured using the hydrogen clearance method with acutely implanted platinum electrodes. Hypoxia (PaO2 35.3 +/- 2.4 Torr) and hypercapnia (PaCO2 68.1 +/- 5.1 Torr) increased basal CBF from 76.3 +/- 9.0 ml/100g/min to 168.1 +/- 20.1 ml/100g/min and 162.4 +/- 31.9 ml/100g/min respectively. The sulphonylurea tolbutamide (1mM in 1%DMSO) had no significant effect on CBF in hyperoxia or in hypercapnia. However, it attenuated the increase of CBF during hypoxia by 66 +/- 11% (p < 0.01). This suggests that opening of tolbutamide-sensitive potassium channels may be involved in the process of hypoxic vasodilation in the rat cerebral cortex.
研究了麻醉大鼠在缺氧和高碳酸血症期间大脑皮质血流的增加情况。使用急性植入的铂电极通过氢清除法测量脑血流量（CBF）。缺氧（动脉血氧分压[PaO₂] 35.3±2.4托）和高碳酸血症（动脉血二氧化碳分压[PaCO₂] 68.1±5.1托）分别使基础CBF从76.3±9.0毫升/100克/分钟增加到168.1±20.1毫升/100克/分钟和162.4±31.9毫升/100克/分钟。磺酰脲类药物甲苯磺丁脲（在1%二甲基亚砜中为1毫摩尔）在高氧或高碳酸血症时对CBF无显著影响。然而，它使缺氧期间CBF的增加减少了66±11%（p<0.01）。这表明甲苯磺丁脲敏感钾通道的开放可能参与了大鼠大脑皮质缺氧性血管舒张过程。
