Basic Research
Copyright ©The Author(s) 2002. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Apr 15, 2002; 8(2): 328-332
Published online Apr 15, 2002. doi: 10.3748/wjg.v8.i2.328
Effect of L-NAME on nitric oxide and gastrointestinal motility alterations in cirrhotic rats
Xin Wang, Yue-Xia Zhong, Zong-You Zhang, Ju Lu, Mei Lan, Ji-Yan Miao, Xue-Gang Guo, Yong-Quan Shi, Yan-Qiu Zhao, Jie Ding, Kai-Cun Wu, Bo-Rong Pan, Dai-Ming Fan
Xin Wang, Zong-You Zhang, Mei Lan, Ji-Yan Miao, Xue-Gang Guo, Yong-Quan Shi, Yan-Qiu Zhao, Jie Ding, Kai-Cun Wu, Dai-Ming Fan, Institute of Digestive disease, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
Yue-Xia Zhong, Emergency Department, Tangdu Hospital, Fourth Military Medical University, Xi'an 710038, Shaanxi Province, China
Ju Lu, Class EE 87, Department of Electronic Engineering, Tsinghua University, Beijing 100084, China
Bo-Rong Pan, Oncology Center, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
Author contributions: All authors contributed equally to the work.
Supported by National Natural Science Foundation of China, No.39970901
Correspondence to: Prof. Dai-Ming Fan, Institute of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi'an 710033, Shaanxi Province, China. daimfan@pub.xaonline.com
Telephone: +86-29-3375221 Fax: +86-29-2539041
Received: August 23, 2001
Revised: September 1, 2001
Accepted: September 5, 2001
Published online: April 15, 2002
Abstract

AIM: To investigate the effect of L-NAME on nitric oxide and gastrointestinal motility alterations in cirrhotic rats.

METHODS: Rats with cirrhosis induced by carbon tetrachloride were randomly divided into two groups, one (n = 13) receiving

0.5 mg·kg-1 per day of N G-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor, for 10 d, whereas the other group (n = 13) and control (n = 10) rats were administrated the same volume of 9 g•L⁻¹ saline. Half gastric emptying time and 2 h residual rate were measured by SPECT, using 99mTc-DTPA-labeled barium sulfate as test meal. Gastrointestinal transition time was recorded simultaneously. Serum concentration of nitric oxide (NO) was determined by the kinetic cadmium reduction and colorimetric methods. Immunohistochemical SABC method was used to observe the expression and distribution of three types of nitric oxide synthase (NOS) isoforms in the rat gastrointestinal tract. Western blot was used to detect expression of gastrointestinal NOS isoforms.

RESULTS: Half gastric emptying time and trans-gastrointestinal time were significantly prolonged (124.0 ± 26.4 min; 33.7 ± 8.9 min; 72.1 ± 15.3 min; P < 0.01), (12.4 ± 0.5 h; 9.5 ± 0.3 h; 8.2 ± 0.8 h; P < 0.01), 2 h residual rate was raised in cirrhotic rats than in controls and cirrhotic rats treated with L-NAME (54.9% ± 7.6%, 13.7% ± 3.2%, 34.9% ± 10.3%, P < 0.01). Serum concentration of NO was significantly increased in cirrhotic rats than in the other groups (8.20 ± 2.48) μmol•L⁻¹, (5.94 ± 1.07) μmol•L⁻¹, and control (5.66 ± 1.60) μmol•L⁻¹, P < 0.01. NOS staining intensities which were mainly located in the gastrointestinal tissues were markedly lower in cirrhotic rats than in the controls and cirrhotic rats after treated with L-NAME.

CONCLUSION: Gastrointestinal motility was remarkably inhibited in cirrhotic rats, which could be alleviated by L-NAME.Nitric oxide may play an important role in the inhibition of gastrointestinal motility in cirrhotic rats.

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