Basic Research
Copyright ©2006 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Jul 21, 2006; 12(27): 4364-4368
Published online Jul 21, 2006. doi: 10.3748/wjg.v12.i27.4364
Role of neuronal nitric oxide synthase and inducible nitric oxide synthase in intestinal injury in neonatal rats
Hui Lu, Bing Zhu, Xin-Dong Xue
Hui Lu, Xin-Dong Xue, Department of Pediatrics, the Second Affiliated Hospital of China Medical University, Shenyang 110004, Liaoning Province, China
Bing Zhu, Department of Cardiac Surgery, the Second Affiliated Hospital of China Medical University, Shenyang 110004, Liaoning Province, China
Correspondence to: Dr. Hui Lu, Associate Professor, Department of Pediatrics, the Second Affiliated Hospital of China Medical University, 36 Sanhao Street, Heping District, Shenyang 110004, Liaoning Province, China. luhui6699@sina.com
Telephone: +86-13575789528
Received: April 3, 2006
Revised: April 20, 2006
Accepted: April 24, 2006
Published online: July 21, 2006
Abstract

AIM: To investigate the dynamic change and role of neuronal nitric oxide synthase (nNOS) and inducible nitric oxide synthase (iNOS) in neonatal rat with intestinal injury and to define whether necrotizing enterocolitis (NEC) is associated with the levels of nitric oxide synthase (NOS) in the mucosa of the affected intestine tissue.

METHODS: Wistar rats less than 24 h in age received an intraperitoneal injection with 5 mg/kg lipopolysaccharide (LPS). Ileum tissues were collected at 1, 3, 6, 12 and 24 h following LPS challenge for histological evaluation of NEC and for measurements of nNOS and iNOS. The correlation between the degree of intestinal injury and levels of NOS was determined.

RESULTS: The LPS-injected pups showed a significant increase in injury scores versus the control. The expression of nNOS protein and mRNA was diminished after LPS injection. There was a negative significant correlation between the nNOS protein and the grade of median intestinal injury within 24 h. The expression of iNOS protein and mRNA was significantly increased in the peak of intestinal injury.

CONCLUSION: nNOS and iNOS play different roles in LPS-induced intestinal injury. Caution should be exerted concerning potential therapeutic uses of NOS inhibitors in NEC.

Keywords: Neuronal nitric oxide synthase; Inducible nitric oxide synthase; Necrotizing enterocolitis; Rat; Newborn