Evaluation of omental inflammatory response with P-/E-selectin levels and histopathologic findings in experimental...

The omentum plays a crucial role in abdominal defense mechanism by adhering to sites of inflammation and absorbing bacteria and debris from the peritoneal cavity. An experimental study was conducted to evaluate the inflammatory response of omentum in different abdominal events with omental P-/E-selectin levels and histopathologic findings.

Thirty Wistar rats were placed into 5 groups (n = 6), including a control group (CG), sham group (SG), bladder perforation (BP) group, splenic laceration (SL) group, and cecal ligation and puncture (CLP) group. Omental samples were obtained in CG after median laparotomy. In accordance with described models, BP, SL, and CLP were performed in experimental groups. Twenty-four hours after the first laparotomy, localization of the omental pad was noted, and omental samples were obtained for biochemical analysis of levels and histopathologic findings (no. of vessels in sections, polymorphic nuclear leukocytes [PMLs], lymphocytes). The mean P-/E-selectin levels and histopathologic findings of inflammation were compared between groups.

Although omentum was adhered to the cecum in all subjects after CLP, similar findings were not detected in other groups. P-selectin and E-selectin levels and number of PML were significantly increased in the CLP group when compared with other groups (P < .05). The number of vessels in sections was significantly increased in CLP group when compared with SG and BP groups (P < .05), and the BP group had a decreased number of vessels than CG (P < .05). The number of PML was significantly increased in SG and SL and BP groups with respect to CG (P < .05).

Among different experimental intraabdominal catastrophes, only CLP caused an inflammatory response and increased levels of adhesion molecules in the omentum. These findings suggest that the nature of the inflammation is the main determining factor for the omental function in intraabdominal events.