Using the hydrogen clearance technique, we have measured blood flow in the sciatic nerves of healthy, anaesthetized rats at rest, at various arterial blood pressures, and during respiratory acidosis and hypoxia. The majority of hydrogen clearance curves were bi-exponential. The slower component appears to reflect nerve blood flow more accurately than either the fast component or the composite value obtained from both components. Mean nerve blood flow estimated from the slow component of the seventeen bi-exponential hydrogen clearance curves and from the seven mono-exponential curves was 15.8 +/- 1.1 ml min-1 100 g-1 (+/- S.E. of the mean). The mean value of the fast component of the bi-exponential curves was 118 +/- 6 ml min-1 100 g-1 and that obtained from both components was 25.9 +/- 2.6 ml min-1 100 g-1. Sciatic nerve blood flow was measured over a range of arterial blood pressures of 60-160 mmHG. There is a curvilinear relationship between pressure and flow suggesting that the nerve vascular bed responds passively to changes in perfusion pressure. Respiratory acidosis resulted in no significant change in nerve blood flow. The mean flow was 15.5 +/- 1.9 ml min-1 100 g-1. During hypoxia, nerve blood flow decreased to 7.5 +/- 1.4 ml min-1 100 g-1 as a result of a reduction in arterial blood pressure and an increase in vascular resistance. These findings suggest that normal nerve blood flow is high in relation to metabolic activity, especially when compared with the brain.
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机译：使用氢清除技术，我们测量了健康，麻醉的大鼠在静止，各种动脉血压以及呼吸性酸中毒和低氧期间的坐骨神经中的血流量。大部分氢清除曲线是双指数的。比起快速分量或从这两个分量获得的综合值，慢速分量似乎更准确地反映了神经血流。根据17条双指数氢清除曲线的慢速分量和7条单指数曲线估计的平均神经血流量为15.8 +/- 1.1 ml min-1 100 g-1（平均值的+/- S.E.）。双指数曲线的快速成分的平均值为118 +/- 6 ml min-1 100 g-1，从这两种成分获得的平均值为25.9 +/- 2.6 ml min-1 100 g-1。在60-160 mmHG的一系列动脉血压范围内测量坐骨神经的血流量。压力与流量之间存在曲线关系，表明神经血管床对灌注压力的变化被动响应。呼吸性酸中毒导致神经血流没有明显变化。平均流量为15.5 +/- 1.9 ml min-1 100 g-1。在缺氧期间，由于动脉血压的降低和血管阻力的增加，神经血流量降至7.5 +/- 1.4 ml min-1 100 g-1。这些发现表明，正常的神经血流与代谢活动有关，尤其是与大脑相比。
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