摘要
AIM： To investigate the response of astrocytes and neurons in rat lumbo±sacral spinal cord and medulla oblongata induced by chronic colonic inflammation, and the relationship between them. METHODS： Thirty-three male Sprague-Dawley rats were randomly divided into two groups： experimental group （n = 17）, colonic inflammation was induced by intra-luminal administration of trinitrobenzenesulfonic acid （TNBS）; control group （n = 16）, saline was administered intra-luminally. After 3, 7, 14, and 28 d of administration, the lumbo-sacral spinal cord and medulla oblongata were removed and processed for anti-glial fibrillary acidic protein （GFAP）, Fos and GFAP/Fos immunohistochemistry. RESULTS： Activated astrocytes positive for GFAP were mainly distributed in the superficial laminae （laminae Ⅰ-Ⅱ） of dorsal horn, intermediolateral nucleus （laminae Ⅴ）, posterior commissural nucleus （laminae Ⅹ） and anterolateral nucleus （laminae Ⅸ）. Fos-IR （Fos-immunoreactive） neurons were mainly distributed in the deeper laminae of the spinal cord （laminae Ⅲ-Ⅳ, Ⅴ-Ⅵ）. In the medulla oblongata, both GFAP-IR astrocytes and Fos-IR neurons were mainly distributed in the medullary visceral zone （MVZ）. The density of GFAP in the spinal cord of experimental rats was significantly higher after 3, 7, and 14 d of TNBS administration compared with the controls （50.44±16.8, 29.24±6.5, 24.14±5.6, P〈0.05）. The density of GFAP in MVZ was significantly higher after 3 d of TNBS administration （34.34±2.5, P〈0.05）. After 28 d of TNBS administration, the density of GFAP in the spinal cord and MVZ decreased and became comparable to that of the controls （18.04±4.9, 14.64±6.4, P〉0.05）. CONCLUSION： Astrocytes in spinal cord and medulla oblongata can be activated by colonic inflammation. The activated astrocytes are closely related to Fos-IR neurons. With the recovery of colonic inflammation, the activity ofastrocytes in the spinal cord and medulla oblongata is reduced.
AIM:- To investigate the response of astrocytes and neurons in rat lumbo-sacral spinal cord and medulla oblongata induced by chronic colonic inflammation, and the relationship between them.METHODS: Thirty-three male Sprague-Dawley rats were randomly divided into two groups: experimental group (n = 17), colonic inflammation was induced by intra-luminal administration of trinitrobenzenesulfonic acid (TNBS);control group (n = 16), saline was administered intra-luminally.After 3, 7, 14, and 28 d of administration, the lumbo-sacral spinal cord and medulla oblongata were removed and processed for anti-glial fibrillary acidic protein (GFAP),Fos and GFAP/Fos immunohistochemistry.RESULTS: Activated astrocytes positive for GFAP were mainly distributed in the superficial laminae (laminae Ⅰ-Ⅱ)of dorsal horn, intermediolateral nucleus (laminae V),posterior commissural nucleus (laminae X) and anterolateral nucleus (laminae Ⅸ). Fos-IR (Fos-immunoreactive)neurons were mainly distributed in the deeper laminae of the spinal cord (laminae Ⅲ-Ⅳ, V-Ⅵ). In the medulla oblongata, both GFAP-IR astrocytes and Fos-IR neurons were mainly distributed in the medullary visceral zone (MVZ). The density of GFAP in the spinal cord of experimental rats was significantly higher after 3, 7, and 14 d of TNBS administration compared with the controls (50.4±16.8,29.2±6.5, 24.1±5.6, P＜0.05). The density of GFAP in MVZ was significantly higher after 3 d of TNBS administration (34.3±2.5, P＜0.05). After 28 d of TNBS administration,the density of GFAP in the spinal cord and MVZ decreased and became comparable to that of the controls (18.0±4.9,14.6±6.4, P＞0.05).CONCLUSION: Astrocytes in spinal cord and medulla oblongata can be activated by colonic inflammation. The activated astrocytes are closely related to Fos-IR neurons.With the recovery of colonic inflammation, the activity of astrocytes in the spinal cord and medulla oblongata is reduced.
