Department of Pharmacology, XinJiang Medical University, Urumqi, XinJiang, China.
Parasitology Department, Rouen University Hospital & EA 4311-IFRMP 23, Institute for Biomedical Research, University of Rouen, Rouen, France.
PLoS One. 2018 Mar 9;13(3):e0194058. doi: 10.1371/journal.pone.0194058. eCollection 2018.
Somatostatins are proteins that are involved in gastrointestinal function. However, little is known with regard to somatostatin receptor subtype (SSTR) expression changes that occur in the jejunum during low-grade inflammation and during subsequent octreotide treatment. The aim of the present study was to investigate the expression of SSTRs in the jejunums of Cryptosporidium parvum (C. parvum)-infected rats by immunohistochemisty, reverse transcription (RT) PCR and quantitative real-time RT-PCR assays. Five-day-old suckling Sprague-Dawley rats (n = 15 for each group) were orally gavaged with 105 Nouzilly isolate (NoI) oocysts. Rats then received 50 μg/kg/day of octreotide by intraperitoneal injection from day 10 to day 17 post-infection. Animals were sacrificed on days 7 and 14 post-infection for immunohistochemical analysis and on days 14, 35 and 50 for mRNA expression analysis of SSTR subtypes. Histological analysis of jejunum tissues demonstrated infection of C. parvum along the villus brush border on day 7 post-infection and infection clearance by day 14 post-infection. Real-time PCR analysis indicated that in the inflamed jejunum, a significant increase in SSTR1 and SSTR2 expression was observed on day 14 post-infection. Octreotide therapy down-regulated the expression of SSTR2 on day 37 post-infection but significantly increased expression of SSTR1, SSTR2 and SSTR3 on day 50 post-infection. The results indicate that specific SSTRs may regulate the inflammatory pathway in the rat intestinal inflammation model.
生长抑素是参与胃肠功能的蛋白质。然而，对于在低度炎症期间和随后奥曲肽治疗期间在空肠中发生的生长抑素受体亚型（SSTR）表达变化知之甚少。本研究旨在通过免疫组织化学、逆转录（RT）PCR 和定量实时 RT-PCR 检测来研究隐孢子虫（C. parvum）感染大鼠空肠中 SSTR 的表达。5 日龄乳鼠（每组 15 只）经口灌胃 105 Nouzilly 分离株（NoI）卵囊。然后，从感染后第 10 天到第 17 天，大鼠每天通过腹腔注射 50μg/kg 的奥曲肽。感染后第 7 天和第 14 天处死动物进行免疫组织化学分析，感染后第 14 天、第 35 天和第 50 天进行 SSTR 亚型 mRNA 表达分析。空肠组织的组织学分析表明，感染后第 7 天 C. parvum 沿绒毛刷状缘感染，第 14 天感染清除。实时 PCR 分析表明，在炎症性空肠中，感染后第 14 天 SSTR1 和 SSTR2 的表达显著增加。奥曲肽治疗可在感染后第 37 天下调 SSTR2 的表达，但在感染后第 50 天可显著增加 SSTR1、SSTR2 和 SSTR3 的表达。结果表明，特定的 SSTR 可能调节大鼠肠道炎症模型中的炎症途径。
