Cogswell A M, Johnson P J, Adams H R
Department of Veterinary Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia 65211, USA.
Am J Vet Res. 1995 Dec;56(12):1637-41.
To test the hypothesis that endothelium-derived nitric oxide modulates vasomotor reactivity in equine digital arteries.
Digital arteries were isolated from adult horses, and their vasodilator properties were examined in an in vitro controlled environment.
Five adult horses (1 gelding, 4 mares) without evidence of hoof or vascular disease were studied.
Arterial rings with or without endothelium were exposed to endothelium-dependent vasodilator drugs in the presence or absence of a pharmacologic inhibitor of the enzyme nitric oxide synthase.
Vasodilator effects of 3 endothelium-dependent vasorelaxant agents were significantly greater in endothelium-intact vessels than in endothelium-denuded vessels. Moreover, a nitric oxide synthase inhibitor reduced vasodilator responses to endothelium-dependent vasodilators in endothelium-intact arteries, but had no discernable effects in endothelium-denuded arteries.
These findings indicate the presence of endothelium-derived relaxing factor/nitric oxide in blood vessels of horses, and identify vascular endothelium as an endogenous modulator of vasomotor tone in the digital arteries of this species.
验证内皮源性一氧化氮调节马趾动脉血管舒缩反应性的假说。
从成年马分离出趾动脉，并在体外控制环境中检测其血管舒张特性。
研究了5匹无蹄部或血管疾病迹象的成年马（1匹 gelding，4匹母马）。
将有或无内皮的动脉环在有或无一氧化氮合酶药理抑制剂的情况下，暴露于内皮依赖性血管舒张药物。
3种内皮依赖性血管舒张剂对有内皮血管的舒张作用显著大于去内皮血管。此外，一氧化氮合酶抑制剂降低了有内皮动脉对内皮依赖性血管舒张剂的舒张反应，但对去内皮动脉无明显影响。
这些发现表明马血管中存在内皮源性舒张因子/一氧化氮，并确定血管内皮是该物种趾动脉血管舒缩张力 的内源性调节因子。
