Objective:To investigate the effects of Da-Cheng-Qi Decoction (DCQD,大承气汤) combined with Lactobacillus acidophilus (LA) on the recovery of gastrointestinal (GI) function in traumatic brain-injured (TBI)mice.Methods:A total of 150 male C57BL/6 mice were randomly divided into sham-injury,normal saline (NS),DCQD (0.4 mL/day),LA (≥1 × 1010 cfu/day LA),DCQD+LA (LA administration at the same dosage after 4 h of feeding DCQD),and 1/2 DCQD+LA groups (LA administration at the same dosage after 4 h of feeding 1/2 DCQD dose) by a random number table,5-8 mice in each group.The sever TBI model was constructed according to Feeney's enhanced gravitational forces of free falling.On days 1,3,and 7 post-TBI,plasma diamine oxidase(DAO) and D-lactic acid levels were assessed by enzyme-linked immunosorbent assay (ELISA).Occludin expression in the intestinal epithelium was assessed by Westem blot analysis.Transmission electron microscopy(TEM) was used to observe the morphological changes in the network structure of interstitial cells of Cajal (ICC)and change of enteric nervous system-ICC-smooth muscle cell (ENS-ICC-SMC).Immunofluorescence staining was used to detect changes in the network structure of the ICC.Results:Compared with the NS group,occludin expression in the DCQD+LA group significantly increased on Day 1,3,and 7 post-TBI (P＜0.05 or P＜0.01).The concentration of DAO significantly decreased in the LA,DCQD,and DCQD+LA groups on Day 3 and 7,whilst the D-lactate concentrations in the LA and 1/2 DCQD+LA groups decreased on Day 1 and 3 post-injury(P＜0.05 or P＜0.01).The NS group experienced a great damage on the ENS-ICC-SMC network morphology and ICC network structure,and all treatment groups had some improvements,among which the DCQD+LA group presented relatively intact network morphology.Conclusions:DCQD combined with LA treatment could effectively repair the intestinal mucosal barrier and improve GI motility in mice after TBI.The combination of DCQD and LA was more effective than their respective monotherapies.