诱导型一氧化氮合酶在啮齿动物术后肠道平滑肌功能障碍中的作用。

Role of inducible nitric oxide synthase in postoperative intestinal smooth muscle dysfunction in rodents.

作者信息

Kalff J C, Schraut W H, Billiar T R, Simmons R L, Bauer A J

机构信息

Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania 15261, USA.

出版信息

Gastroenterology. 2000 Feb;118(2):316-27. doi: 10.1016/s0016-5085(00)70214-9.

DOI:10.1016/s0016-5085(00)70214-9

PMID:10648460

Abstract

BACKGROUND & AIMS: We have shown that intestinal manipulation leads to a significant inhibition of circular muscle contraction. We hypothesized that the inflammatory mediator inducible nitric oxide (NO) plays a role in surgically induced ileus.

METHODS

Rats and inducible NO synthase (iNOS) knockout and wild-type mice underwent a simple intestinal manipulation. Reverse-transcription polymerase chain reaction and immunohistochemistry were used to detect and localize iNOS expression. Nitrite and NO production were measured in muscularis cultures. Spontaneous and bethanechol-stimulated jejunal circular muscle contractions were measured in an organ bath.

RESULTS

Intestinal manipulation resulted in significant iNOS messenger RNA induction in mucosa and muscularis. Immunohistochemistry localized iNOS in phagocytes within the muscularis. Nitrite and NO production increased 59.8-fold 24 hours after manipulation. L-n(6)-(1-iminoethyl) lysine (L-NIL) inhibited this response. In control rats, selective iNOS inhibition did not increase spontaneous muscle activity, but after manipulation L-NIL significantly improved spontaneous activity. iNOS knockout mice showed a significant 81% decrease in neutrophil infiltration into the muscularis after intestinal manipulation compared with wild-types. Contractile activity was normal in knockout mice after intestinal manipulation.

CONCLUSIONS

These results show that leukocyte-derived inducible NO inhibits gastrointestinal motility after manipulation and plays an essential role in the initiation of intestinal inflammation.

摘要

背景与目的

我们已经表明，肠道操作会导致环形肌收缩受到显著抑制。我们推测炎症介质诱导型一氧化氮（NO）在手术引起的肠梗阻中起作用。

方法

对大鼠以及诱导型一氧化氮合酶（iNOS）基因敲除小鼠和野生型小鼠进行简单的肠道操作。采用逆转录聚合酶链反应和免疫组织化学方法检测并定位iNOS的表达。在肌层培养物中测量亚硝酸盐和NO的生成。在器官浴槽中测量空肠环形肌的自发收缩和氨甲酰甲胆碱刺激的收缩。

结果

肠道操作导致黏膜和肌层中iNOS信使核糖核酸显著诱导。免疫组织化学将iNOS定位在肌层内的吞噬细胞中。操作后24小时，亚硝酸盐和NO的生成增加了59.8倍。L - n(6)-(1 - 亚氨基乙基)赖氨酸（L - NIL）抑制了这种反应。在对照大鼠中，选择性iNOS抑制并未增加自发肌肉活动，但在操作后，L - NIL显著改善了自发活动。与野生型相比，iNOS基因敲除小鼠在肠道操作后肌层中中性粒细胞浸润显著减少81%。肠道操作后基因敲除小鼠的收缩活性正常。