Department of Orthopedic Surgery, Kobe University Graduate School of Medicine, Kobe University, Kobe, Hyogo, Japan.
PLoS One. 2011;6(9):e24137. doi: 10.1371/journal.pone.0024137. Epub 2011 Sep 8.
Carbon dioxide (CO(2)) therapy refers to the transcutaneous administration of CO(2) for therapeutic purposes. This effect has been explained by an increase in the pressure of O(2) in tissues known as the Bohr effect. However, there have been no reports investigating the oxygen dissociation of haemoglobin (Hb) during transcutaneous application of CO(2)in vivo. In this study, we investigate whether the Bohr effect is caused by transcutaneous application of CO2 in human living body.
We used a novel system for transcutaneous application of CO(2) using pure CO(2) gas, hydrogel, and a plastic adaptor. The validity of the CO(2) hydrogel was confirmed in vitro using a measuring device for transcutaneous CO(2) absorption using rat skin. Next, we measured the pH change in the human triceps surae muscle during transcutaneous application of CO(2) using phosphorus-31 magnetic resonance spectroscopy ((31)P-MRS) in vivo. In addition, oxy- and deoxy-Hb concentrations were measured with near-infrared spectroscopy in the human arm with occulted blood flow to investigate O2 dissociation from Hb caused by transcutaneous application of CO(2).
The rat skin experiment showed that CO(2) hydrogel enhanced CO(2) gas permeation through the rat skin. The intracellular pH of the triceps surae muscle decreased significantly 10 min. after transcutaneous application of CO(2). The NIRS data show the oxy-Hb concentration decreased significantly 4 min. after CO(2) application, and deoxy-Hb concentration increased significantly 2 min. after CO(2) application in the CO(2)-applied group compared to the control group. Oxy-Hb concentration significantly decreased while deoxy-Hb concentration significantly increased after transcutaneous CO(2) application.
Our novel transcutaneous CO(2) application facilitated an O(2) dissociation from Hb in the human body, thus providing evidence of the Bohr effect in vivo.
二氧化碳（CO₂）治疗是指经皮给予 CO₂以达到治疗目的。这种效应可以通过增加组织中氧气的压力来解释，即波尔效应。然而，目前还没有研究报告调查在体内经皮应用 CO₂时血红蛋白（Hb）的氧离解。在这项研究中，我们调查了经皮应用 CO₂是否会引起人体中的波尔效应。
我们使用一种新的系统，通过纯 CO₂气体、水凝胶和塑料适配器进行经皮 CO₂应用。使用一种测量装置在体外确认 CO₂水凝胶的有效性，该装置用于测量大鼠皮肤的经皮 CO₂吸收。接下来，我们使用磷-31 磁共振波谱学（31P-MRS）在体内测量人三头肌在经皮应用 CO₂期间的 pH 值变化。此外，我们使用近红外光谱法测量被遮挡血流的人手臂中的氧合和脱氧 Hb 浓度，以研究经皮应用 CO₂引起的 Hb 中 O₂的离解。
大鼠皮肤实验表明，CO₂水凝胶增强了 CO₂气体通过大鼠皮肤的渗透。经皮应用 CO₂ 10 分钟后，三头肌的细胞内 pH 值显著降低。NIRS 数据显示，与对照组相比，CO₂ 应用后 4 分钟，氧合 Hb 浓度显著降低，2 分钟后脱氧 Hb 浓度显著升高。CO₂ 应用后，氧合 Hb 浓度显著降低，脱氧 Hb 浓度显著升高。
我们新的经皮 CO₂应用促进了人体中 Hb 的 O₂离解，从而为体内的波尔效应提供了证据。
