Experimental Laparotomy in Mice

Experimental laparotomy was performed as previously described with minor modifications [23 (link)]. Briefly, mice were anesthetized with 2.0% isoflurane (Baxter Healthcare, Puerto Rico, USA) for 2 min, and anesthesia was maintained with 1.4% isoflurane. Mice were placed on a heating pad to maintain body temperature between 36.5–37.0 °C. After the hair was shaved and the surgical field was disinfected, an approximately 1-cm median incision was made 0.5–1 cm below the xiphoid, and approximately 5 cm of the small intestine was gently pulled out and then exposed to sterile gauze presoaked with normal saline. After being rubbed for 10 min, the intestine was returned to the abdomen. The muscle and skin were closed layer-by-layer with 5–0 absorbable sutures (Polysorb, COVIDIEN, USA). Finally, 0.1 ml 0.2% lidocaine was injected subcutaneously for postoperative analgesia. The mice were allowed to recover in an incubator at 35 °C for 30 min before being returned to their home cages.