The pathogenesis of Strongylus vulgaris-mediated equine cranial mesenteric arteritis /
| Main Author: | |
|---|---|
| Other Authors: | , , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1988.
|
| Subjects: | |
| Online Access: | Link to ProQuest copy Link to OAKTrust copy ProQuest, Abstract |
| Abstract: | The pathogenesis of S. vulgaris-mediated equine cranial mesenteric arteritis was evaluated by means of histologic, morphometric, biochemical, and in vitro (tissue culture) studies. Thorough understanding of all three of these phases was considered to be of importance in elucidation of the pathogenesis of the arteritis. Histologic examination revealed that thrombosis and the severity of inflammation varied on a seasonal basis and was directly associated with larval presence. Intimal and adventitial fibrosis were generally of greater severity than medial fibrosis. Fibrosis of the vasa vasorum was less frequent than fibrosis of the artery itself. Morphometry revealed a significant increase in intimal, adventitial, and to a lesser extent, medial thickness in affected as compared to normal arteries. This change was due to the accumulation of collagen and was considered to result in decreased arterial elasticity. The luminal diameter varied widely among affected arteries. Biochemical alterations included a marked increase in collagen in the affected as compared to the normal arteries, substantiating the histological observations. Additionally, there was an increase in the hydroxylysine:hydroxyproline ratio in the affected as compared to normal arteries, suggesting that the collagen cross linking may be altered. In vitro analysis centered primarily around the factor(s) which stimulate smooth muscle cell proliferation and/or collagen production that were considered to likely play a role in the pathogenesis of the lesion. Some of the factors found to stimulate proliferation include equine platelet factors, S. vulgaris larval extract, and conditioned media from equine mononuclear cells. Also, S. vulgaris larval extract induced a marked dose-dependent blastogenic response in equine lymphocytes. Although various factors were concluded to be involved in the pathogenesis of cranial mesenteric arteritis, S. vulgaris larvae were considered to be of central importance. The sequence of events in the pathogenesis of the lesion were larval invasion, thrombosis, intimal inflammatory cell infiltration and fibrosis, internal elastic lamina disruption, medial inflammatory cell infiltration and fibrosis, and fibrosis of the vasa vasorum. |
|---|---|
| Item Description: | "Major subject: Veterinary Pathology." Typescript (photocopy). Vita. |
| Physical Description: | xvii, 218 leaves : illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references (leaves 199-217). |