Monteiro A A, Svensson H, Bornmyr S, Arborelius M, Kopp S
Department of Clinical Oral Physiology, School of Dentistry, Karolinska Institutet, Huddinge, Sweden.
Arch Oral Biol. 1989;34(10):779-86. doi: 10.1016/0003-9969(89)90028-9.
Changes induced by 30 s of isometric contraction at 10% and 50% of the maximum voluntary contraction were assessed in 10 healthy subjects; there was a median increase of 1.8 and 0.3 times in 133Xe clearance and 5.3 and 2.7 times in laser Doppler flowmetry. In the first minute after 10% maximum voluntary contraction, 133Xe clearance increased 12.1 times in relation to the initial resting level, and flowmetry values decreased to become 3.5 times higher than the basal flow; corresponding values after 50% maximum voluntary contraction were 24.3 times and 3.7 times. From the second minute after contraction, there was a rapid decrease in 133Xe clearance and a slow decrease in flowmetry values. Five minutes after biting at 10% maximum voluntary contraction, both methods showed a total net increase of about 15 times; after biting at 50% maximum voluntary contraction the corresponding values were 38 and 23 times. Thus laser Doppler flowmetry can be used to assess changes in blood flow in the masseter; it registers a greater increase in flow during isometric contraction than does 133Xe clearance. The significant difference between methods immediately after either chosen level of contraction disappears when the total net post-contraction hyperaemia is assessed over a period of 2 and 5 min, respectively.
在10名健康受试者中评估了在最大自主收缩的10%和50%下进行30秒等长收缩所引起的变化；133Xe清除率分别增加了1.8倍和0.3倍，激光多普勒血流仪测量值分别增加了5.3倍和2.7倍。在最大自主收缩的10%之后的第一分钟内，133Xe清除率相对于初始静息水平增加了12.1倍，血流仪测量值下降至比基础血流高3.5倍；最大自主收缩的50%之后的相应值分别为24.3倍和3.7倍。从收缩后的第二分钟开始，133Xe清除率迅速下降，血流仪测量值缓慢下降。在最大自主收缩的10%咬肌收缩五分钟后，两种方法均显示总净增加约15倍；在最大自主收缩的50%咬肌收缩后，相应值分别为38倍和23倍。因此，激光多普勒血流仪可用于评估咬肌血流的变化；在等长收缩期间，它记录的血流增加幅度比133Xe清除率更大。当分别在2分钟和5分钟的时间段内评估收缩后总的净充血情况时，在任何选定收缩水平后立即出现的两种方法之间的显著差异就消失了。
