Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
Acta Physiol (Oxf). 2018 Sep;224(1):e13080. doi: 10.1111/apha.13080. Epub 2018 May 16.
Nitric oxide (NO) importantly contributes to cardiovascular homeostasis by regulating blood flow and maintaining endothelial integrity. Conversely, reduced NO bioavailability is a central feature during natural ageing and in many cardiovascular disorders, including hypertension. The inorganic anions nitrate and nitrite are endogenously formed after oxidation of NO synthase (NOS)-derived NO and are also present in our daily diet. Knowledge accumulated over the past two decades has demonstrated that these anions can be recycled back to NO and other bioactive nitrogen oxides via serial reductions that involve oral commensal bacteria and various enzymatic systems. Intake of inorganic nitrate, which is predominantly found in green leafy vegetables and beets, has a variety of favourable cardiovascular effects. As hypertension is a major risk factor of morbidity and mortality worldwide, much attention has been paid to the blood pressure reducing effect of inorganic nitrate. Here, we describe how dietary nitrate, via stimulation of the nitrate-nitrite-NO pathway, affects various organ systems and discuss underlying mechanisms that may contribute to the observed blood pressure-lowering effect.
一氧化氮（NO）通过调节血流量和维持内皮完整性，对心血管稳态起着重要作用。相反，NO 生物利用度降低是自然衰老和许多心血管疾病（包括高血压）的一个核心特征。无机阴离子硝酸盐和亚硝酸盐是在一氧化氮合酶（NOS）衍生的 NO 氧化后内源性形成的，也存在于我们的日常饮食中。过去二十年积累的知识表明，这些阴离子可以通过涉及口腔共生细菌和各种酶系统的连续还原反应，再循环回 NO 和其他生物活性氮氧化物。无机硝酸盐的摄入主要存在于绿叶蔬菜和甜菜中，对心血管有多种有益作用。由于高血压是全球发病率和死亡率的主要危险因素，因此人们非常关注无机硝酸盐的降血压作用。在这里，我们描述了饮食中的硝酸盐如何通过刺激硝酸盐-亚硝酸盐-NO 途径来影响各种器官系统，并讨论了可能有助于观察到的降压作用的潜在机制。
