D Ellsbury | PubMed Health

PubMed1993

Absorption in the isolated bowel segment.

An isolated bowel segment (IBS) is a viable mesenteric segment of intestine. This study was undertaken to investigate the effects of mesenteric vascular and neural supply on intestinal absorption. Ten rats were used for leucine absorption and another 10 for glucose absorption experiments. L-leucine, 12 ml of 15.0 mM/L, or 3.0 mM/L of D-glucose solution were recirculated through the IBS (n = 5) and rat jejunum that underwent sham operation (n = 5) at 2.56 ml/min for 90 min. Absorption was expressed as millimoles of leucine or glucose per gram of mucosal protein. The Student's t test was used for statistical analysis; a p < or = 0.05 was considered significant. The net absorption of L-leucine was 36.20 +/- 3.31 mM/g of mucosal protein in the IBS and 15.52 +/- 1.48 mM/g of mucosal protein in the control group (p < 0.001). The net absorption of D-glucose was 3.82 +/- 0.26 mM/g of mucosal protein in the experimental group and 4.34 +/- 0.31 mM/g of mucosal protein in the control group (p = 0.02). This study concludes that absorption of leucine and glucose in the IBS is preserved after mesenteric division.

Animals↗

PubMed1992

The isolated bowel segment (Iowa model II): motility across the anastomosis with or without mesenteric division.

In previous reports, anastomosis has been shown to disrupt the myoelectric activity of the bowel. However, these studies have failed to delineate the role of the extrinsic nerves. Using an isolated bowel segment (IBS) and an amesenteric bowel segment (ABS), motility was evaluated by myoelectric recording across a bowel anastomosis. Ten rats were divided equally into the experimental group with the IBS and the control group with the ABS. In the IBS group, an 8-cm segment of jejunum was divided, reanastomosed, and coapted to the liver margin (Iowa model II). In the ABS group, an 8-cm segment of jejunum was coapted to the liver margin without disruption of bowel continuity (Iowa model II variant). Two weeks later, bipolar electrodes were implanted in the IBS and ABS, and normal jejunum in both groups. Mesenteric division (MD) was performed 4 weeks later to eliminate extrinsic innervation. Myoelectrical recordings were taken 2 weeks before and after MD. In the control group with IBS, incoordination in the propagation of the migrating motor complex (MMC) and reduction in the frequency of slow waves (FSW) were observed across the anastomosis and were unchanged by MD. In the control group with the ABS, the MMC and FSW were identical to that in the normal jejunum and were unaffected by MD. In both groups postprandial inhibition of the MMC was the same as in the normal jejunum and was unaffected by MD. This study confirms that incoordination in propagation of the MMC and reduction in FSW occur across a bowel anastomosis, and elimination of extrinsic innervation does not affect the autonomy of these changes.(ABSTRACT TRUNCATED AT 250 WORDS)

Anastomosis, Surgical↗