一氧化氮(NO)是一种具有活跃生物化学性质的无机小分子,普遍存在于脊椎动物各种细胞内.随着1987年揭示内皮衍生舒张因子本质即一氧化氮,NO的生物学作用引起了人们极大关注,并逐渐成为医学与生物学研究的热点.NO作为第二信使和神经递质,是细胞间信息传递的重要调节因子,而且也是介导细胞免疫和细胞毒性的重要物质,与许多疾病的发生发展关系密切.现就近年来有关NO在肺癌免疫方面的研究作一综述.1 NO的酶性合成NO最早发现于巨噬细胞(MФ),在生物体内NO是由NO合酶(NOS)催化L-精氨酸胍基末端上的氮氧化而成,NOS主要有两种类型:基础型NOS(Consititutive NOS,cNOS)和诱导型NOS(Induced NOS,iNOS).肺内.cNOS主要位于肺血管内皮细胞、气管上皮细胞、血小板、白细胞及非肾上腺能非胆碱能神经元等.在生理情况下肺内cNOS处于转录、翻译和催化NO合成状态,但此时NO产量较低,主要维持肺血管、气道平滑肌的舒张以及神经信息的传递等.缺氧可抑制cNOS表达,这与缺氧引起的肺动脉高压密切相 Nitric oxide (NO) is an inorganic small molecule with active biochemical properties that is ubiquitous in various cells of vertebrates. With the discovery in 1987 of the essence of endothelium-derived relaxing factor, nitric oxide, the biological effects of NO People pay great attention and gradually become a hotspot in medical and biological research. As a second messenger and neurotransmitter, NO is an important regulator of cell-to-cell information transmission, and it is also an important substance that mediates cellular immunity and cytotoxicity. It is closely related to the occurrence and development of many diseases. Now there is a review on the research of NO in lung cancer immunity in recent years. 1 The NO synthesis of NO was first discovered in macrophages (MФ), and in vivo, NO is caused by NO synthase. (NOS) catalyzes the oxidation of nitrogen at the end of the thiol group of L-arginine. There are two major types of NOS: basal NOS (cNOS) and inducible NOS (iNOS). Intrapulmonary .cNOS Mainly located in pulmonary vascular endothelial cells, tracheal epithelial cells, platelets, leukocytes, and non-adrenergic non-cholinergic neurons. Under physiological conditions, cNOS in the lung is in the state of transcription, translation, and catalytic NO synthesis, but at this time, the production of NO is low. ,the Lord Maintaining pulmonary blood vessels, relaxation of airway smooth muscle, etc. and the transmission of neural information. CNOS inhibit the expression of hypoxia, hypoxia-induced pulmonary hypertension which are closely