Genecin P, Polio J, Groszmann R J
Hepatic Hemodynamic Laboratory, Veterans Administration Medical Center, West Haven, Connecticut 06516.
Am J Physiol. 1990 Sep;259(3 Pt 1):G498-503. doi: 10.1152/ajpgi.1990.259.3.G498.
Expansion of plasma volume may be necessary for the development of the hyperdynamic circulation in portal hypertension. In experiment 1, sham portal vein-constricted (sham PVL) rats were divided into normal diet (NL diet sham) and low-sodium diet (low-Na sham) groups. Data obtained from the NL diet sham group was used as control data in studying portal hypertensive rats, which were also divided into normal diet (NL diet PVL) and sodium-restricted (low-Na PVL) groups on the day of portal vein constriction. There were no hemodynamic differences at 3 wk between sham PVL rats on the two diets. In contrast, sodium restriction in PVL rats resulted in a significant amelioration of the hyperdynamic circulation. In experiment 2, PVL rats were fed a normal diet for 10 days, followed by allocation to NL diet PVL and low-Na PVL groups. The hemodynamic effects of sodium restriction in these animals (studied at 22 and 28 days after PVL) were similar to those observed in experiment 1. A time course for amelioration of the hyperdynamic circulation in PVL rats by sodium restriction is described. Sodium restriction prevents the expansion of the plasma volume in PVL rats. Interference with plasma volume expansion blunts the development of (and can ameliorate) the hyperdynamic syndrome. Plasma volume expansion seems necessary for the development of the hyperdynamic circulation in portal hypertension.
血浆容量的扩充可能是门静脉高压时高动力循环发展所必需的。在实验1中，假门静脉缩窄（假PVL）大鼠被分为正常饮食（NL饮食假手术组）和低钠饮食（低钠假手术组）组。从NL饮食假手术组获得的数据用作研究门静脉高压大鼠的对照数据，门静脉缩窄当天，门静脉高压大鼠也被分为正常饮食（NL饮食PVL组）和限钠（低钠PVL组）组。两种饮食的假PVL大鼠在3周时血流动力学无差异。相反，PVL大鼠的限钠导致高动力循环明显改善。在实验2中，PVL大鼠先给予正常饮食10天，然后分为NL饮食PVL组和低钠PVL组。这些动物（在PVL后22天和28天研究）限钠的血流动力学效应与实验1中观察到的相似。描述了限钠改善PVL大鼠高动力循环的时间进程。限钠可防止PVL大鼠血浆容量的扩充。干扰血浆容量扩充可减弱（并可改善）高动力综合征的发展。血浆容量扩充似乎是门静脉高压时高动力循环发展所必需的。
