Sevillano S, De la Mano A M, De Dios I, Ramudo L, Manso M A
Department of Physiology and Pharmacology, University of Salamanca, Salamanca, Spain.
Digestion. 2003;68(1):34-40. doi: 10.1159/000073223. Epub 2003 Aug 29.
To analyze the capability of N-acetylcysteine (NAC) to prevent major intra-acinar pathogenic mechanisms involved in the development of acute pancreatitis (AP).
AP was induced by pancreatic duct obstruction (PDO) in rats. Some animals received NAC (50 mg/kg) 1 h before and 1 h after PDO. During a 24-hour period of PDO, plasma amylase activity and pancreatic glutathione and malondialdehyde levels were measured. Cytosolic Ca(2+) levels and enzyme (amylase and trypsinogen) load in acinar cells were also analyzed by flow cytometry, and histological analysis of the pancreas was performed by electron microscopy.
NAC avoided glutathione depletion at early AP stages, thereby preventing pancreatic oxidative damage, as reflected by normal malondialdehyde levels. By limiting oxidative stress, NAC treatment effectively prevented the impairment of Ca(2+) homeostasis found in acinar cells from early AP onwards, thus protecting the pancreas from damage. In addition, lower quantities of digestive enzymes were accumulated within acinar cells. This finding, together with the significantly lower hyperamylasemia observed in these animals, suggests that NAC treatment palliates the exocytosis blockade induced by PDO.
By preventing oxidative stress at early AP stages, NAC administration prevents other pathological mechanisms of AP from being developed inside acinar cells, thus palliating the severity of disease.
分析N-乙酰半胱氨酸(NAC)预防急性胰腺炎(AP)发生过程中主要腺泡内致病机制的能力。
通过大鼠胰管阻塞(PDO)诱导AP。一些动物在PDO前1小时和后1小时接受NAC(50mg/kg)。在PDO的24小时期间,测量血浆淀粉酶活性以及胰腺中谷胱甘肽和丙二醛水平。还通过流式细胞术分析腺泡细胞中的胞质Ca(2+)水平和酶(淀粉酶和胰蛋白酶原)含量,并通过电子显微镜对胰腺进行组织学分析。
NAC避免了AP早期阶段的谷胱甘肽耗竭,从而防止了胰腺氧化损伤,丙二醛水平正常即反映了这一点。通过限制氧化应激,NAC治疗有效地预防了从AP早期起在腺泡细胞中发现的Ca(2+)稳态受损,从而保护胰腺免受损伤。此外,腺泡细胞内积累的消化酶数量减少。这一发现,连同在这些动物中观察到的明显较低的高淀粉酶血症,表明NAC治疗减轻了PDO诱导的胞吐作用阻断。
通过在AP早期预防氧化应激,NAC给药可防止AP的其他病理机制在腺泡细胞内发展,从而减轻疾病的严重程度。