Mills D E, Mah M, Ward R P, Morris B L, Floras J S
Department of Health Studies, University of Waterloo, Ontario, Canada.
Am J Physiol. 1990 Dec;259(6 Pt 2):R1164-71. doi: 10.1152/ajpregu.1990.259.6.R1164.
The effects of dietary safflower (control, n = 10), borage (n = 9), and fish oil (n = 10), as sources of linoleic, gamma-linolenic, and eicosapentaenoic acid, respectively, at a dose of 4.5 ml/day for 4 wk, on cardiovascular responses to lower body negative pressure (LBNP) were studied in normotensive humans in a randomized, double-blind design. Pre- and postsupplementation, subjects were exposed to 5 min of -10 and -40 mmHg LBNP. Blood pressure (BP), heart rate (HR), forearm blood flow (FBF), forearm vascular resistance (FVR), and plasma norepinephrine (PNE) were measured at each level. Subjects were then exposed to a cold-pressor test, isometric handgrip, and forearm ischemia. At pretest, LBNP reduced BP and FBF and increased HR and FVR in all groups. After diets, the PNE and vasoconstrictor responses to -40 mmHg LBNP, as well as the reflex vasodilation on its cessation, were significantly augmented by borage oil. No diet differences were observed in the HR responses to LBNP or in the responses to the other tasks, with the exception that fish oil increased FBF after forearm ischemia. These data indicate that borage oil augments the arterial baroreflex control of vascular resistance. The vasodilatory effects of fish oil may be mediated via local mechanisms.
在一项随机、双盲设计中，研究了以膳食红花油（对照组，n = 10）、琉璃苣油（n = 9）和鱼油（n = 10）分别作为亚油酸、γ-亚麻酸和二十碳五烯酸的来源，以4.5毫升/天的剂量服用4周，对血压正常的人在进行下体负压（LBNP）时心血管反应的影响。在补充前和补充后，受试者分别接受5分钟-10 mmHg和-40 mmHg的LBNP。在每个水平测量血压（BP）、心率（HR）、前臂血流量（FBF）、前臂血管阻力（FVR）和血浆去甲肾上腺素（PNE）。然后，受试者接受冷加压试验、等长握力试验和前臂缺血试验。在试验前，LBNP使所有组的血压和FBF降低，使HR和FVR升高。饮食后，琉璃苣油显著增强了对-40 mmHg LBNP的PNE和血管收缩反应，以及在其停止时的反射性血管舒张。在对LBNP的HR反应或对其他任务的反应中，未观察到饮食差异，但鱼油在前臂缺血后增加了FBF。这些数据表明，琉璃苣油增强了动脉压力反射对血管阻力的控制。鱼油的血管舒张作用可能是通过局部机制介导的。
