Universidade Federal do Rio Grande do Sul, Programa de Pós Graduação em Ciências Biológicas: Fisiologia. Brazil.
Instituto de Tecnologia do Paraná-TECPAR.
Ann Hepatol. 2014 May-Jun;13(3):370-7.
Portal hypertension is a clinical syndrome associated with the development of a hyperdynamic circulation and gastroesophageal varices. Aim. To evaluate the antioxidant effect of N-acetylcysteine on portal hypertensive rats.
Portal hypertension was induced by partial portal vein ligation (PPVL). Oxidative damage in the stomach was measured by lipoperoxidation trough thiobarbituric acid reactive substances (TBARS) and antioxidant enzyme activity; we also evaluated nitrates and nitrites level and histology stained by hematoxylin-eosin. We performed evaluation of portal pressure and measurement of vessels diameter. Liver damage was evaluated by measuring hepatic enzymes. The animals were divided in four experimental groups (n = 6): Sham-operated (SO), SO + NAC, Partial portal vein ligation (PPVL) and PPVL + NAC. N-acetylcysteine (10 mg/kg ip) was administered daily for 7 days and started 8 days after surgery.
The portal hypertensive group showed an increase in portal pressure, vessels diameter, levels of TBARS and nitrates and nitrites when compared to SO group. These values were accompanied by a decrease in superoxide dismutase (SOD) and glutathione peroxidase (GPx) antioxidant enzyme activity. Histology showed dilated vessels in the gastric mucosa in the PPVL group. NAC was able to decrease portal pressure values, vessels diameter, TBARS and also nitrates and nitrites levels when compared to PPVL group. Furthermore, PPVL+NAC group presented an increase in SOD and GPx activity. N-acetylcysteine attenuated damage in gastric mucosa.
Oxidative stress is associated with portal hypertension and that antioxidant NAC is able to minimize damages of PPVL in rats.
门静脉高压症是一种与高动力循环和胃食管静脉曲张发展相关的临床综合征。目的：评估 N-乙酰半胱氨酸对门静脉高压大鼠的抗氧化作用。
通过部分门静脉结扎（PPVL）诱导门静脉高压。通过硫代巴比妥酸反应性物质（TBARS）和抗氧化酶活性测量胃中的脂质过氧化损伤；我们还评估了硝酸盐和亚硝酸盐水平以及苏木精-伊红染色的组织学。我们进行了门静脉压力评估和血管直径测量。通过测量肝酶评估肝损伤。将动物分为四组（每组 n = 6）：假手术（SO）、SO+NAC、部分门静脉结扎（PPVL）和 PPVL+NAC。N-乙酰半胱氨酸（10mg/kg ip）每天给药 7 天，并在手术后 8 天开始。
与 SO 组相比，门静脉高压组的门静脉压力、血管直径、TBARS 和硝酸盐及亚硝酸盐水平升高。这些值伴随着超氧化物歧化酶（SOD）和谷胱甘肽过氧化物酶（GPx）抗氧化酶活性降低。组织学显示 PPVL 组胃黏膜扩张的血管。与 PPVL 组相比，NAC 能够降低门静脉压力值、血管直径、TBARS 以及硝酸盐和亚硝酸盐水平。此外，PPVL+NAC 组的 SOD 和 GPx 活性增加。N-乙酰半胱氨酸减轻了胃黏膜的损伤。
氧化应激与门静脉高压相关，抗氧化剂 NAC 能够减轻大鼠 PPVL 的损伤。
