Department of Kinesiology and Applied Physiology, Newark, DE 19716, USA.
Exp Physiol. 2011 Jul;96(7):674-80. doi: 10.1113/expphysiol.2011.058404. Epub 2011 May 13.
We tested the hypothesis that microdialysis of hypertonic saline would attenuate the skin blood flow response to local heating. Seventeen healthy subjects (23 ± 1 years old) were studied. In one group (n = 9), four microdialysis fibres were placed in the forearm skin and infused with the following: (1) Ringer solution; (2) normal saline (0.9% NaCl); (3) hypertonic saline (3% NaCl); and (4) 10 mm l-NAME. A second group (n = 8) was infused with the following: (1) normal saline; (2) hypertonic saline; (3) normal saline + l-NAME; and (4) hypertonic saline + l-NAME. Red blood cell flux was measured via laser Doppler flowmetry during local heating to 42°C. Site-specific maximal vasodilatation was determined by infusing 28 mm sodium nitroprusside while the skin was heated to 43°C. Data were expressed as the percentage of maximal cutaneous vascular conductance (%CVC(max)). The local heating response at the Ringer solution and normal saline sites did not differ (n = 9; initial peak Ringer solution, 69 ± 6 versus normal saline, 66 ± 2%CVC(max); plateau Ringer solution, 89 ± 4 versus normal saline, 89 ± 5%CVC(max)). Hypertonic saline reduced the initial peak (n = 9; normal saline, 66 ± 2 versus hypertonic saline, 54 ± 4%CVC(max); P < 0.05) and plateau (normal saline, 89 ± 5 versus hypertonic saline, 78 ± 2%CVC(max); P < 0.05) compared with normal saline. Plateau %CVC(max) was attenuated to a similar value at the normal saline + l-NAME and hypertonic saline + l-NAME sites (n = 8; normal saline + l-NAME, 39 ± 6 and hypertonic saline + l-NAME, 39 ± 5%CVC(max)). The nitric oxide contribution (plateau %CVC(max) - l-NAME plateau %CVC(max)) was lower at the hypertonic saline site (normal saline, 55 ± 6 versus hypertonic saline, 35 ± 4; P < 0.01). These data suggest an effect of salt on the cutaneous response to local heating, which may be mediated through a decreased production and/or availability of nitric oxide.
我们测试了这样一个假设，即高渗盐水的微透析会减弱局部加热引起的皮肤血流反应。17 名健康受试者（23 ± 1 岁）参与了研究。在一组（n = 9）中，四个微透析纤维被放置在前臂皮肤中，并分别用以下物质进行灌注：（1）林格氏液；（2）生理盐水（0.9%NaCl）；（3）高渗盐水（3%NaCl）；和（4）10mM l-NAME。第二组（n = 8）被分别用以下物质进行灌注：（1）生理盐水；（2）高渗盐水；（3）生理盐水 + l-NAME；和（4）高渗盐水 + l-NAME。在局部加热至 42°C 时，通过激光多普勒血流仪测量红细胞通量。通过在皮肤加热至 43°C 时输注 28mm 硝普钠来确定局部最大血管扩张程度。数据表示为最大皮肤血管传导率的百分比（%CVC(max)）。林格氏液和生理盐水部位的局部加热反应没有差异（n = 9；初始峰值林格氏液，69 ± 6% versus 生理盐水，66 ± 2% CVC(max)；林格氏液平台期，89 ± 4% versus 生理盐水，89 ± 5% CVC(max)）。高渗盐水降低了初始峰值（n = 9；生理盐水，66 ± 2% versus 高渗盐水，54 ± 4% CVC(max)；P < 0.05）和平台期（生理盐水，89 ± 5% versus 高渗盐水，78 ± 2% CVC(max)；P < 0.05）与生理盐水相比。与生理盐水 + l-NAME 和高渗盐水 + l-NAME 部位的生理盐水相比，平台期的 %CVC(max)被类似地降低（n = 8；生理盐水 + l-NAME，39 ± 6% 和高渗盐水 + l-NAME，39 ± 5% CVC(max)）。高渗盐水部位的一氧化氮贡献（平台期 %CVC(max) - l-NAME 平台期 %CVC(max)）较低（生理盐水，55 ± 6% versus 高渗盐水，35 ± 4%；P < 0.01）。这些数据表明盐对局部加热引起的皮肤反应有影响，这可能是通过降低一氧化氮的产生和/或可利用性来介导的。
