Relationship between Gastrointestinal Peptides, Intestinal Wall Compliance, and Vascular Resistance
Abstract
Numerous peptides have been isolated from the wall of the gastrointestinal tract. Among the actions reported for these peptides are effects on vascular or intestinal smooth muscle. Yet, few reports cite the simultaneous actions of these peptides on both types of muscle. Thus, their vasoactivity in the intestine may be under or over-estimated. Therefore, the aim of this investigation was to ascertain the simultaneous effects of local intraarterial infusions of synthetic gastrointestinal peptides on both Intestinal vascular and visceral smooth muscle. Studies were designed to indicate which peptides may be involved in the postprandial changes in ileal vascular and visceral smooth muscle. The experiments conducted allowed for the concurrent assessment of vascular resistance and Ileal wall compliance. Previously fasted adult mongrel dogs were anesthetized, intubated and ventilated, A midline incision was produced through the abdomen and a segment of ileum exteriorized. The segmental artery was isolated and the ileum perfused at constant flow with arterial blood obtained from a cannulated femoral artery. Perfusion pressure was measured from the ileal perfusion circuit through a needle-tipped catheter. Systemic pressure was measured from the contralateral femoral artery. Incisions were made at both ends of the exteriorized segment and a balloon-tipped catheter inserted into the ileum to allow changes in Ileal volume and measurement of ileal Intraluminal pressure. Adjacent segments were ligated and the mesentery cut to exclude collateral blood flow. Ileal wall compliance was determined by measuring the changes In intraluminal pressure produced by stepwise Increases in luminal volume, AV/AP. An increase in compliance was considered to reflect a decrease in wall tension, while a decrease in compliance reflected an Increase in tension. Changes in vascular resistance were Inferred from changes in ileal perfusion pressure.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 20, 1983
- Accession Number
- AD1010658
Entities
People
- Andre J. Premen
Organizations
- Uniformed Services University of the Health Sciences