Metzler-Wilson Kristen, Kellie Lesley A, Tomc Christa, Simpson Chris, Sammons Dawn, Wilson Thad E
Ohio Musculoskeletal and Neurologic Institute, Ohio University, Athens, OH 45701, USA.
Clin Physiol Funct Imaging. 2012 Sep;32(5):361-6. doi: 10.1111/j.1475-097X.2012.01137.x. Epub 2012 Apr 12.
Local heating induces biphasic cutaneous vasodilation in non-glabrous skin of the forearm. However, little data exist in other skin regions, despite the prevalence of facial flushing disorders. We hypothesized that facial skin will have greater initial peak responses to local heating than forearm skin because of neural differences between sites and, furthermore, axon reflex vasodilation will be eliminated in facial sites with sensory blockade.
Skin blood flow (laser-Doppler flowmetry) responses of healthy, non-obese subjects to local heating (32-42°C in ~5 min, held 40 min) in the forehead (n = 22), cheek (n = 22), forearm (n = 22) and palm (n = 13) were expressed as percentage of maximum cutaneous vascular conductance (CVC; flux/mean arterial pressure). In an additional group (n = 7), sensation was blocked (topical prilocaine-lidocaine) prior to the local heating protocol.
Prior to heating, CVC differences were noted (forearm = 10 ± 3, cheek = 19 ± 3, forehead = 16 ± 1 and palm = 65 ± 11%CVC; P<0·05). Initial peak CVC was similar between forehead, cheek and forearm (85 ± 3, 92 ± 2, and 91 ± 6%CVC, respectively), but elevated in the palm (120 ± 8%CVC; P<0·05). Compared to facial control sites, sensory blockade delayed increases in both cheek and forehead (P<0·05) CVC but did not change magnitude of the biphasic response (P>0·05).
These data indicate that facial skin initial CVC peaks to local heating are similar to non-glabrous skin. In contrast to forearm responses, facial topical sensory blockade does not abate axon reflex responses to local heating. Palm skin data indicate that maximal skin blood flow is not obtained during local heating as it is in non-glabrous skin.
局部加热可引起前臂非无毛皮肤出现双相性皮肤血管舒张。然而，尽管面部潮红障碍普遍存在，但其他皮肤区域的数据却很少。我们推测，由于不同部位的神经差异，面部皮肤对局部加热的初始峰值反应会比前臂皮肤更大，此外，在感觉被阻断的面部部位，轴突反射性血管舒张将被消除。
健康非肥胖受试者的皮肤血流（激光多普勒血流仪）对前额（n = 22）、脸颊（n = 22）、前臂（n = 22）和手掌（n = 13）局部加热（在约5分钟内从32°C升至42°C，保持40分钟）的反应，以最大皮肤血管传导率（CVC；血流量/平均动脉压）的百分比表示。在另一组（n = 7）中，在局部加热方案之前阻断感觉（局部使用丙胺卡因-利多卡因）。
加热前，观察到CVC存在差异（前臂 = 10 ± 3、脸颊 = 19 ± 3、前额 = 16 ± 1、手掌 = 65 ± 11%CVC；P<0·05）。前额、脸颊和前臂的初始峰值CVC相似（分别为85 ± 3、92 ± 2和91 ± 6%CVC），但手掌的CVC升高（120 ± 8%CVC；P<0·05）。与面部对照部位相比，感觉阻断延迟了脸颊和前额CVC的升高（P<0·05），但未改变双相反应的幅度（P>0·05）。
这些数据表明，面部皮肤对局部加热的初始CVC峰值与非无毛皮肤相似。与前臂反应不同，面部局部感觉阻断不会减弱对局部加热的轴突反射反应。手掌皮肤数据表明，局部加热期间未获得如非无毛皮肤那样的最大皮肤血流量。
