Ultrastructural mucosal injury after experimental ischemia of the ascending colon in horses.

J. R. Snyder, J. R. Pascoe, H. J. Olander, F. A. Harmon, D. M. Hinds, N. J. Vatistasa, W. S. Tyler

Research output: Contribution to journalArticlepeer-review

19 Scopus citations


The ultrastructural injury that develops sequentially in the ascending colon during experimentally induced ischemia was examined in 6 halothane-anesthetized horses. Colonic ischemia was created by 2 types of vascular occlusion 24 cm proximal and distal to the pelvic flexure. In all horses, transmural vascular compression was created. The colonic venous circulation was obstructed in 3 horses, whereas in the other 3 horses, arterial and venous circulation was obstructed. Two additional horses were anesthetized as controls for determination of any morphologic alterations associated with the experimental protocol. Full-thickness colonic biopsy specimens were obtained from the antimesenteric border of the pelvic flexure at 0, 0.25, 0.5, 1, 1.5, 1.75, 2, 2.25, 2.5, 3, 3.5, 4, 4.5, and 5 hours during occlusion, and were studied by light and transmission electron microscopy. Morphologic alterations did not develop in the colon of control horses. Mucosal congestion was observed by light microscopy in the colon of horses with experimentally induced ischemia, but congestion developed early in those with obstructed colonic venous circulation, compared with those having arterial and venous obstruction. Inter- and intracellular vacuolation and loss of staining initially resulted in groups of 3 to 5 superficial luminal epithelial cells. Alterations in the glandular epithelium lagged behind those in the superficial epithelium, but were observed in both groups by 2 hours of obstruction. These changes progressed to 100% sloughing of all epithelium by 4.5 to 5 hours. The initial cellular alterations, which were observed by transmission electron microscopy, developed at 0.25 hour in horses with colonic venous obstruction and was characterized by inter- and intracellular edema.(ABSTRACT TRUNCATED AT 250 WORDS)

Original languageEnglish (US)
Pages (from-to)1917-1924
Number of pages8
JournalAmerican Journal of Veterinary Research
Issue number10
StatePublished - Oct 1 1992
Externally publishedYes

ASJC Scopus subject areas

  • veterinary(all)


Dive into the research topics of 'Ultrastructural mucosal injury after experimental ischemia of the ascending colon in horses.'. Together they form a unique fingerprint.

Cite this