Use of an extracorporeal circuit to evaluate effects of intraluminal distention and decompression on the equine jejunum

Jorge E. Nieto Comparative Gastrointestinal Laboratory, Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA 95616.

Search for other papers by Jorge E. Nieto in
Current site
Google Scholar
PubMed
Close
 MVZ
,
Linda M. Van Hoogmoed Comparative Gastrointestinal Laboratory, Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA 95616.

Search for other papers by Linda M. Van Hoogmoed in
Current site
Google Scholar
PubMed
Close
 DVM, PhD
,
Sharon J. Spier Comparative Gastrointestinal Laboratory, Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616.

Search for other papers by Sharon J. Spier in
Current site
Google Scholar
PubMed
Close
 DVM, PhD
,
Nicholas J. Vatistas Comparative Gastrointestinal Laboratory, Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA 95616.

Search for other papers by Nicholas J. Vatistas in
Current site
Google Scholar
PubMed
Close
 DVM, PhD
,
Jack R. Snyder Comparative Gastrointestinal Laboratory, Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA 95616.

Search for other papers by Jack R. Snyder in
Current site
Google Scholar
PubMed
Close
 DVM, PhD
, and
Brenna L. Timmerman Comparative Gastrointestinal Laboratory, Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA 95616.

Search for other papers by Brenna L. Timmerman in
Current site
Google Scholar
PubMed
Close
 BS

Click on author name to view affiliation information

Abstract

Objective—To use an extracorporeal circuit to evaluate effects of intraluminal distention on the jejunum of healthy horses.

Sample Population—2 jejunal segments from each of 5 horses.

Procedure—Jejunal segments were harvested and maintained in an extracorporeal circuit. One segment was subjected to distention (intraluminal pressure, 25 cm H2O) followed by decompression, and 1 segment was maintained without distention. The influence of distention-decompression on vascular resistance was calculated. Mucosal permeability was evaluated by measuring the clearance of albumin from blood to lumen. After distention and decompression, tissue specimens were collected for histomorphologic evaluation. In addition, the contractile response of the circular smooth muscle layer was determined following incubation with 3 prokinetic agents.

Results—Intestinal vascular resistance increased during intraluminal distention and returned to baseline values after decompression. Albumin clearance rate increased after distention, compared with baseline and control values. Histologic examination of the distended segments revealed grade-1 and -2 lesions of the mucosal villus. Edema and hemorrhage were evident in the submucosa and muscular layers. Mesothelial cell loss, edema, and hemorrhage were also evident in the serosa. Mucosal surface area and villus tip height decreased and submucosal volume increased in the distended tissue. Compared with responses in control specimens, distention decreased the contractile response induced by cisapride, erythromycin, and metoclopramide.

Conclusions and Clinical Relevance—Intraluminal distention of the jejunum followed by decompression increased mucosal permeability and injury and decreased responses to prokinetic agents. Horses with intraluminal intestinal distention may have a decreased response to prokinetic agents. (Am J Vet Res 2002;63:267–275)

Abstract

Objective—To use an extracorporeal circuit to evaluate effects of intraluminal distention on the jejunum of healthy horses.

Sample Population—2 jejunal segments from each of 5 horses.

Procedure—Jejunal segments were harvested and maintained in an extracorporeal circuit. One segment was subjected to distention (intraluminal pressure, 25 cm H2O) followed by decompression, and 1 segment was maintained without distention. The influence of distention-decompression on vascular resistance was calculated. Mucosal permeability was evaluated by measuring the clearance of albumin from blood to lumen. After distention and decompression, tissue specimens were collected for histomorphologic evaluation. In addition, the contractile response of the circular smooth muscle layer was determined following incubation with 3 prokinetic agents.

Results—Intestinal vascular resistance increased during intraluminal distention and returned to baseline values after decompression. Albumin clearance rate increased after distention, compared with baseline and control values. Histologic examination of the distended segments revealed grade-1 and -2 lesions of the mucosal villus. Edema and hemorrhage were evident in the submucosa and muscular layers. Mesothelial cell loss, edema, and hemorrhage were also evident in the serosa. Mucosal surface area and villus tip height decreased and submucosal volume increased in the distended tissue. Compared with responses in control specimens, distention decreased the contractile response induced by cisapride, erythromycin, and metoclopramide.

Conclusions and Clinical Relevance—Intraluminal distention of the jejunum followed by decompression increased mucosal permeability and injury and decreased responses to prokinetic agents. Horses with intraluminal intestinal distention may have a decreased response to prokinetic agents. (Am J Vet Res 2002;63:267–275)

All Time Past Year Past 30 Days
Abstract Views 36 0 0
Full Text Views 157 103 7
PDF Downloads 86 62 4
Advertisement