Collins Nicole, Brewer Matthias
Departments of *Anesthesiology †Chemistry, The University of Vermont, Burlington, VT.
J Neurosurg Anesthesiol. 2015 Jul;27(3):257-61. doi: 10.1097/ANA.0000000000000150.
Gasotransmitters are endogenously made, biologically active gases with unique physiological properties. In addition to participation in the hypoxic respiratory reflex of the carotid body, the gasotransmitter hydrogen sulfide (H(2)S) is thought to play a role in more localized vasodilatory hypoxic tissue responses. This pilot project describes a methodology suitable to the clinical environment that allows for H(2)S gas capture in human plasma utilizing the fluorescent trapping agent dansyl azide.
Under an IRB-approved pilot project, 10 healthy male volunteers were spontaneously ventilated on room air, hypoxic (15% oxygen, 85% nitrogen), and hyperoxic (100%) gas mixtures through a nonrebreather system. Venous whole-blood samples were collected at both internal jugular and antecubital sites following 7 minutes of exposure to the tested oxygen environments. Resultant plasma aliquots were treated with dansyl azide and submitted to fluorescence reading (excitation 340 nm, emission 517 nm).
Compiled mean data from volunteer plasma samples demonstrated statistically significant findings (P<0.05) in measurement of increased fluorescent intensity between those samples collected under mildly hypoxic conditions compared with normoxic and hyperoxic samples submitted to the same laboratory criteria.
To study the role of H(2)S as a marker of hypoxic response in humans, a reliable, robust, and safe protocol amenable to standard hospital laboratory procedures is needed. Through modification to methodologies described in the biochemistry literature, this pilot project demonstrates the feasibility of utilizing a fluorescent H2S gas trapping agent for assessment of hypoxic response in humans within the confines of a typical clinical collection and analysis environment.
气体递质是内源性产生的具有独特生理特性的生物活性气体。除了参与颈动脉体的低氧呼吸反射外，气体递质硫化氢（H₂S）还被认为在更局部的血管舒张性低氧组织反应中发挥作用。本试点项目描述了一种适用于临床环境的方法，该方法利用荧光捕获剂丹磺酰叠氮化物在人血浆中捕获H₂S气体。
在一项经机构审查委员会批准的试点项目中，10名健康男性志愿者通过无重复呼吸系统在室内空气、低氧（15%氧气，85%氮气）和高氧（100%）气体混合物环境下自主呼吸。在暴露于测试的氧气环境7分钟后，于颈内静脉和肘前部位采集静脉全血样本。所得血浆等分试样用丹磺酰叠氮化物处理，并进行荧光读数（激发波长340nm，发射波长517nm）。
来自志愿者血浆样本的汇总平均数据显示，与在相同实验室标准下的常氧和高氧样本相比，在轻度低氧条件下采集的样本中荧光强度增加的测量结果具有统计学意义（P<0.05）。
为了研究H₂S作为人类低氧反应标志物的作用，需要一种适用于标准医院实验室程序的可靠、稳健且安全的方案。通过对生物化学文献中描述的方法进行改进，本试点项目证明了在典型的临床采集和分析环境范围内，利用荧光H₂S气体捕获剂评估人类低氧反应的可行性。
