Donald John A, Broughton Brad R S
School of Biological and Chemical Sciences, Deakin University, Geelong, Victoria 3217, Australia.
Comp Biochem Physiol A Mol Integr Physiol. 2005 Oct;142(2):188-97. doi: 10.1016/j.cbpa.2005.07.015. Epub 2005 Aug 31.
In mammals, much is understood about the endothelial and neural NO control mechanisms in the vasculature. In contrast, NO control of blood vessels in lower vertebrates is poorly understood, with the majority of research focusing on the presence of an endothelial NO system; however, its presence remains controversial. This study examined the mechanisms by which NO regulates the large blood vessels of non-mammalian vertebrates. In all species examined, the arteries and veins contained a plexus of NOS-positive perivascular nerves that included nerve bundles and fine, varicose nerve terminals. However, in the large arteries and veins of various species of fishes and amphibians, no anatomical evidence was found for endothelial NOS using both NADPH-diaphorase and eNOS immunohistochemistry. In contrast, perinuclear NOS staining was readily apparent in blue-tongue lizard, pigeon and rat, which suggested that eNOS first appeared in reptiles. Physiological analysis of NO signalling in the vascular smooth muscle of short-finned eel and cane toad could not find any evidence for endothelial NO signalling. In contrast, it appears that activation of the nitrergic vasomotor nerves is responsible for NO control of the blood vessels.
在哺乳动物中，我们对脉管系统中内皮和神经一氧化氮（NO）的控制机制已有很多了解。相比之下，对于低等脊椎动物血管中NO的控制机制却知之甚少，大多数研究都集中在内皮型NO系统的存在上；然而，其存在仍存在争议。本研究探讨了NO调节非哺乳动物脊椎动物大血管的机制。在所研究的所有物种中，动脉和静脉都含有一氧化氮合酶（NOS）阳性的血管周围神经丛，其中包括神经束和细小的、有曲张的神经末梢。然而，在各种鱼类和两栖类动物的大动脉和静脉中，使用还原型辅酶Ⅱ黄递酶（NADPH-d）和内皮型一氧化氮合酶（eNOS）免疫组织化学方法均未发现内皮型NOS的解剖学证据。相反，在蓝舌蜥蜴、鸽子和大鼠中，核周NOS染色很明显，这表明eNOS最早出现在爬行动物中。对短鳍鳗和蔗蟾蜍血管平滑肌中NO信号的生理学分析未发现任何内皮型NO信号的证据。相反，似乎是含氮能的血管运动神经的激活负责血管的NO控制。
