Nitric oxide: first in a new class of neurotransmitters.
Nitric oxide: first in a new class of neurotransmitters.
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一氧化氮：第一种新型神经递质。
DOI：
10.1126/science.1353273
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
Snyder,SH
中科院分区：
文献类型：
--
作者：
Snyder,SH
一氧化氮(NO)是一种简单的气体，具有自由基化学性质，但它经常与化学上不同的一氧化二氮N2O混淆，N2O用作麻醉剂，化学上稳定。在细菌中，NO参与固氮，最近被证明在哺乳动物中也有作用。NO是巨噬细胞发挥杀瘤和杀菌作用的信使[1]。当巨噬细胞被内毒素激活时，产生NO，NO合成酶(NOS)的酶显著激活，将精氨酸转化为NO和瓜氨酸。内毒素是一种细菌细胞壁脂多糖，可引起炎症反应。通过去除精氨酸或用一氧化氮合酶抑制剂N-甲基精氨酸抑制NO的形成，可阻断巨噬细胞的杀瘤和杀菌作用。NO也是血管松弛的生理介质。扩张血管的刺激物，如乙酰胆碱、缓激肽和三磷酸腺苷(ATP)，在去除内皮的血管中失去扩张活性(2)。这些介质作用于内皮细胞上的受体，触发“内皮源性松弛因子”(EDRF)的释放，该因子扩散到邻近的平滑肌细胞，引起松弛。EDRF已被明确确定为不是或接近的衍生品
Nitric oxide (NO) is a simple gas with free radical chemical properties, but itis often confused with the chemically distinct nitrous oxide, N2O, which is used as an anesthetic and is chemically stable. In bac-teria NO participates in nitrogen fixation and has recently been shown to function in mammals as well.NO serves as the messenger whereby macrophages exert theirtumoricidal and bactericidal effects (1). When macrophages are activated by endotoxin, a bacterial cell wall lipopolysaccharide that elicits inflammatory responses, the enzyme that makes NO, NO synthase (NOS), which trans-forms arginine into NO and citrulline, is markedly activated. Inhibition of NO for-mation by removal ofarginine or by N-methyl-arginine, an NOSinhibitor, blocks the tumoricidal and bactericidal ac-tions of macrophages. NO is also a physiologic mediator of blood vessel relaxation. Stimuli that dilate blood vessels, such as acetylcholine, bradykinin, and adenosine triphosphate (ATP), lose their vasodilating activity in blood vessels stripped of endothelium (2). These mediators act upon receptors on endothelial cells to trigger the release of an" endothelial-derived relaxing factor"(EDRF), which diffuses to adjacent smooth muscle cells to elicit relaxation. EDRF has been definitively identified as NO or a close derivative that