Mard Seyyed Ali, Mahini Simin, Dianat Mahin, Farbood Yaghoob
Physiology Research Center and Research Center for Infectious Diseases of Digestive System, Department of Physiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
Physiology Research Center and Department. of Physiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
Iran J Basic Med Sci. 2017 Feb;20(2):145-149. doi: 10.22038/ijbms.2017.8237.
Prostaglandins have been shown to mediate the gastro-protective effect of sodium hydrosulfide (NaHS) but effect of NaHS on mRNA expression of prostaglandin E receptors (EP1, 3-4; EPs) has not been investigated. Therefore, this study designed to evaluate the effect of NaHS on mRNA expression of EPs receptors in response to mucosal acidification and distention-induced gastric acid secretion in rats.
Fasted rats were randomly assigned into 4 groups (n=6/group). They were control, and NaHS-treated groups. To evaluate the effect of NaHS on mucosal mRNA expression of EPs receptors, the gastric mucosa exposed to stimulated gastric acid output and mucosal acidification. The pylorus sphincter catheterized for instillation of isotonic neutral saline or acidic solution. Ninety min after beginning the experiments, animals sacrificed and the gastric mucosa collected to determine the pH, mucus secretion and to quantify the mRNA expression of EPs receptors by quantitative real-time PCR.
present results showed that a) NaHS increased the mucus secretion, mRNA expression of EP3 and EP4 receptors in response to distention-induced expression; b) The mRNA expression of EP1 receptors increased while EP4 mRNA receptors decreased in response to mucosal acidification in NaHS-pretreated rats; and c) NaHS increased pH of gastric contents both in response to distention-induced gastric acid secretion and mucosal acidification.
NaHS behaves in a different manner. It effectively only increased the pH of gastric contents to reinforce the gastric mucosa against a highly acidic solution but modulated both acid and mucus secretion when the rate of acid increase in the stomach was slower.
已证实前列腺素介导了硫化氢钠（NaHS）的胃保护作用，但NaHS对前列腺素E受体（EP1、3 - 4；EPs）mRNA表达的影响尚未得到研究。因此，本研究旨在评估NaHS对大鼠黏膜酸化和扩张诱导胃酸分泌时EPs受体mRNA表达的影响。
禁食大鼠随机分为4组（每组n = 6）。分别为对照组和NaHS处理组。为评估NaHS对EPs受体黏膜mRNA表达的影响，使胃黏膜暴露于刺激的胃酸分泌和黏膜酸化环境中。将幽门括约肌插管以滴注等渗中性盐水或酸性溶液。实验开始90分钟后，处死动物并收集胃黏膜，以测定pH值、黏液分泌，并通过定量实时PCR定量EPs受体的mRNA表达。
目前的结果表明：a）NaHS可增加扩张诱导表达时的黏液分泌、EP3和EP4受体的mRNA表达；b）在NaHS预处理的大鼠中，黏膜酸化时EP1受体的mRNA表达增加，而EP4 mRNA受体减少；c）NaHS在扩张诱导胃酸分泌和黏膜酸化时均增加了胃内容物的pH值。
NaHS的作用方式不同。它仅有效地增加了胃内容物的pH值，以增强胃黏膜对高酸性溶液的抵抗力，但在胃内酸增加速率较慢时，可调节酸和黏液分泌。
