Fujita H, Kuwabara H, Reutens D C, Gjedde A
McConnell Brain Imaging Center, Montreal Neurological Institute, Canada.
J Cereb Blood Flow Metab. 1999 Mar;19(3):266-71. doi: 10.1097/00004647-199903000-00004.
The coupling of oxidative metabolism to the blood flow of the sensory motor hand area is uncertain. The authors tested the hypothesis that continued vibrotactile stimulation ultimately must lead to increased oxygen consumption consumption. Twenty-two healthy right-handed young volunteers underwent positron emission tomography (PET) with the [(15)O]water bolus injection method to measure water clearance (K1H2O an index of blood flow (CBF), and with the [(15)O]oxygen bolus inhalation method to measure CMR(O2). The CMR(O2) was measured 30 seconds and 20 minutes after onset of intermittent (1 second on, 1 second off) vibrotactile stimulation (110 Hz) and compared with baseline measurements without stimulation. The K1H2O and CMR(O2) changes (delta K1H2O and delta CMR(O2)) were determined using intersubject averaging, together with magnetic resonance imaging based stereotaxic registration technique. The K1H2O increase was 21 +/- 4% and 12 +/- 4% at 30 seconds and 20 minutes after onset of stimulation, respectively. No significant increase of CMR(O2) was found until 30 minutes after the onset of stimulation. The authors conclude that blood flow and oxidative metabolism undergo uncoupling during sustained phasic stimulation of the sensory hand area. Therefore, neuronal activity stimulated in this manner does not rely on significantly increased oxidative phosphorylation.
感觉运动手部区域的氧化代谢与血流之间的耦合关系尚不确定。作者检验了这样一个假设，即持续的振动触觉刺激最终必然会导致氧消耗增加。22名健康的右利手年轻志愿者采用[（15）O]水团注法进行正电子发射断层扫描（PET）以测量水清除率（K1H2O，血流（CBF）的一个指标），并采用[（15）O]氧团注吸入法测量脑氧代谢率（CMR（O2））。在间歇性（开1秒，关1秒）振动触觉刺激（110Hz）开始后30秒和20分钟测量CMR（O2），并与无刺激时的基线测量值进行比较。使用受试者间平均法以及基于磁共振成像的立体定向配准技术确定K1H2O和CMR（O2）的变化（δK1H2O和δCMR（O2））。刺激开始后30秒和20分钟时，K1H2O分别增加21±4%和12±4%。直到刺激开始后30分钟才发现CMR（O2）有显著增加。作者得出结论，在感觉手部区域的持续阶段性刺激过程中，血流和氧化代谢发生解偶联。因此，以这种方式刺激的神经元活动并不依赖于氧化磷酸化的显著增加。
