Biphasic response to gut manipulation and temporal correlation of cellular infiltrates and muscle dysfunction in rat

Abstract

The functional results demonstrate a biphasic response in the suppression of muscle activity after surgical manipulation. Regression analysis (r2 = 0.998) of the temporal development of leukocyte infiltration and the protracted phase of muscle inhibition provides evidence for a correlation between cellular inflammation and postoperative dysmotility.

Immune mediators of postoperative ileus

“…Additionally, missing parasympathetic innervation was also described. (B) While the twentieth century was mostly dominated by research about inhibitory nerval signaling, first evidence of an immunological response to abdominal surgery was shown by Kalff et al in an animal model of intestinal manipulation after laparotomy in the late 1990s [8][9][10]. In 2003, its relevance was also confirmed in humans [11].…”

“…In rodents, they are abundant in the lamina propria mucosae, the mesentery and the peritoneal cavity, but cannot be detected in the muscularis externa or submucosa of jejujum, ileum and colon while they are abundant in the stomach wall [9,28,29]. In humans, mast cells are present within the lamina propria mucosae (2-3% of all cells) and slightly less in the submucosa (1%) [30].…”

Intestinal Afferent Nerve Sensitivity is Increased During the Initial Development of Postoperative Ileus in Mice

“…One of the most intriguing findings was that at the 9-h time point, segmental dilatation of the small intestine occurred that-to our knowledge-has not been described previously. POI is typically characterized by dilated and flaccid intestine, 8,11,27 but in these previous studies, the early phase of POI was not investigated. One possible explanation is that at the 9-h time point, a transition from an early neuronal period of POI with contracted intestine is Figure 3 a, b Representative afferent nerve and motility recordings in a segment of small intestine from a 3 h sham control animals (a) and from an animal 3 h after induction of postoperative ileus.…”

“…followed by the later period that is known to entail an inflammatory response triggered by immune cells infiltrating the gut wall, 8,11 release of inflammatory mediatory, and intestinal dilation. This interpretation would be consistent with the clinical experience that it takes some time before patients develop a distended abdomen after surgery.…”

“…Then, the animal's small bowel was surgically manipulated in a standardized fashion as described previously. 8 In brief, the small bowel was exteriorized to the left on a moist gauze and was entirely manipulated between two moist cotton applicators for 15 min. After manipulation, the laparotomy was closed with a double-layer running suture.…”