OBJECTIVETo investigate the influence of cervical sympathetic nerve block (SB) on blood flow volume and barrier function of intestinal mucosa after combined radiation and burn injury in rat.

METHODSSD rats were divided into three groups: control (n = 18), combined injury group (n = 100, rats with Co gamma ray body irradiation with a dose of 5 Gy plus 15% TBSA full-thickness burn injury), and combined injury with SB treatment (n = 100, with the same dose of gamma-ray irradiation and burn injury, treated with SB). Twenty rats were sacrificed on 0, 1, 5, 7 days after combined injuries for various observations. SB was conducted with injection of ropivhydrochloride into the neck bilaterally for the SB group, and same amount of normal saline was injected instead in the combined injury group. Blood flow volume, changes in villus height and crypt depth in jejunum, Na(+)-K+ ATPase activity, permeability of small intestine were measured at different time-points.

RESULTSThe blood flow volume in small intestinal mucosal on 1 post-injury days (PID) [(0.29 +/- 0.07) ml x min(-1) x g(-1)] were obviously decreased than that in normal controls [(1.26 +/- 0.23) ml x min(-1) x g(-1), P < 0.01 ], with serious destruction of pit cells, decrease in intestinal mucosal Na(+)-K+ ATPase activity, and increase in intestinal mucosal permeability. Compared with combined injury group, the blood flow volume was [(0.82 +/- 0.11) ml x min(-1) x g(-1) 1 day after combined injury, P < 0.01], and the Na(+)-K+ ATPase activity was obviously increased, and the permeability of small intestine was ameliorated.

CONCLUSIONSB can increase blood flow volume of rat small intestine after combined radiation and burn injury, promote the repair of intestinal epithelium and improve the barrier function of the intestinal wall.