Fos expression in rat lumbarsacral spinal cord and medulla oblongata induced by chronic colonic inflammation / 中华消化杂志

ABSTRACT

Objective The aim of this study was to investigate Fos expression in rat lumbarsacral spinal cord and medulla oblongata induced by chronic colonic inflammation. Methods Twenty six male Sprague Dawley rats were divided into three groups group 1, colonic inflammation was induced in sixteen rats by intraluminal instillation of trinitrobenzenesulfonic acid (TNBS); group 2, saline was instilled intraluminally in eight rats; group 3, no stimulation was given in 2 rats. After 3, 7, 14 and 28 days of instillation, lumbarsacral spinal cord and medulla oblongata were removed and processed for Fos immunohistochemical staining. Results Fos neurons induced by TNBS instillation were mainly distributed in deep laminae (laminae Ⅲ Ⅳ,Ⅴ Ⅵ) in spinal dorsal horn and in medullary visceral zone in medulla oblongata. The number of Fos cells in the spinal cord and medullary visceral zone was significantly higher in rats after 7 and 14 day of TNBS instillation compared with that of controls. After 28 days of TNBS instillation, the number of Fos neurons in the medullary visceral zone decreased and became comparable to that of control group. However, the number of Fos cells (54.1?16.3) in the spinal cord in some rats was still significantly higher than that of controls (12.2 ?2.6, P