硫化氢（H2S）和一氧化氮（NO）是生物系统中重要气体信号分子，发挥相似又相互依赖的生物效应，对血管舒张、神经传导和免疫系统防御都起到调控作用。NO的生物信号通路已被很好的表征，但H2S的生物功能和作用机理仍未被明确阐述。项目旨在研究H2S与NO的化学反应机理从而实现对H2S生物功能及作用机理的深入探索。目前对于H2S和NO化学反应的研究手段仅限于紫外光谱、质谱和15N核磁共振。由于缺乏对反应中间产物结构和化学性质的直接信息，对于反应机理的研究，学术界一直存在争议，所以本项目的研究意义在于：通过17O核磁共振技术捕捉H2S与NO化学反应的中间产物，实现对H2S与NO反应机理的研究，解决目前学术界提出的关于中间产物的某些观点与理论不符的问题，从而对生物系统内H2S的作用机理研究提供理论依据。

Hydrogen sulfide (H2S) and nitric oxide (NO) are important gasotransmitters that are involved in the regulation of many biological and physiological processes, such as the control of blood pressure, neurotransmission and the regulation of the immune system. Despite the importance of H2S, the chemical mechanistic backgrounds that contribute to the biological functions of H2S have not been fully elucidated and thus it becomes the driving force for the further investigations in this discipline. Recent research evidence shows that understanding the fundamental chemistry interplay of H2S and NO signaling pathways is critical for unveil the functions of H2S. Therefore, the aim of this study is to unveil the reaction mechanism between H2S and NO. As the technologies that have been employed for studying the H2S and NO reaction are limited to the UV-Vis, mass spectrometry and 15N NMR measurements, the direct structural information regarding the transient intermediates is lacking, leading to the controversies about the formation of intermediates. This proposal applies an advanced 17O NMR technology to study the reaction mechanism of H2S and NO, thus the reaction intermediates, their chemical properties as well as their functions will be fully accessed. The results obtained will provide theoretical guidance and experiment evidence for explaining the function of H2S in biological system.