Postoperative Ileus Murine Model

Postoperative ileus (POI) is a syndrome that poses a significant challenge in the field of human health, particularly in the management of patients undergoing abdominal surgery. Characterized by delayed recovery of gastrointestinal motility, POI contributes to prolonged hospital stays and increased health care costs, yet no established definition, etiology, or treatment exists¹. Recent research has shed light on the pivotal role of immune cells in the progression of POI^2,3,4, yet further investigation is required to elucidate the underlying mechanisms involved.

In this protocol, we introduce a murine model of POI induced by intra-abdominal surgery, which closely mimics the impact of abdominal surgery on the digestive tract. Our goal was to provide a standardized method for modeling POI in mice, enabling researchers to investigate its pathophysiology and explore novel therapeutic interventions.

The rationale behind the development and utilization of this technique lies in the need for reliable preclinical models to study POI. Traditional approaches to studying POI often lack translational relevance or fail to capture the complex interplay of factors contributing to the condition. By introducing a murine model that closely replicates the clinical scenario, researchers can more accurately investigate the mechanisms underlying POI and test potential therapeutic interventions in a controlled experimental setting.

Compared to alternative techniques, the murine model of POI presented in this protocol offers several advantages. Initially, we integrated our experimental findings with recent advancements to establish a standardized and reproducible protocol for inducing POI in experimental animals. This protocol facilitates consistent assessment of gastrointestinal transit function. Second, employing histological staining and flow cytometry enabled the assessment of tissue swelling, immune cell proliferation, and activation, yielding valuable insights into the inflammatory processes underlying POI⁵.

In the broader context of the literature, establishing a murine model of POI contributes to the expanding body of research aimed at comprehending the pathophysiology of this condition. By bridging the gap between basic science and clinical practice, preclinical models play a pivotal role in developing novel therapeutic strategies for POI⁶. Moreover, the availability of standardized animal models enhances the reproducibility and comparability of research findings across different laboratories. However, this POI model relies on mechanical stimulation during the surgical procedure. Other forms of stimulation-induced ileus may not be suitable for this model. Additionally, researchers should consider factors such as animal welfare regulations, ethical considerations, and resource availability when planning experiments using this model.

In summary, the introduction of a murine model of POI signifies a noteworthy advancement in preclinical research on this debilitating condition. Additionally, we employed H&E staining and flow cytometry to assess tissue swelling and immune cell proliferation and activation. The establishment of a murine POI model would facilitate the discovery of POI mechanisms and promote the development of novel therapies for POI.