Evaluation of platelet activation and platelet-neutrophil aggregates in ponies with alimentary laminitis

Douglas J. Weiss From the Department of Veterinary PathoBiology, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108.

Search for other papers by Douglas J. Weiss in
Current site
Google Scholar
PubMed
Close
 DVM, PhD
,
Oral A. Evanson From the Department of Veterinary PathoBiology, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108.

Search for other papers by Oral A. Evanson in
Current site
Google Scholar
PubMed
Close
 BS
,
David McClenahan From the Department of Veterinary PathoBiology, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108.

Search for other papers by David McClenahan in
Current site
Google Scholar
PubMed
Close
 DVM
,
José J. Fagliari From the Department of Veterinary PathoBiology, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108.

Search for other papers by José J. Fagliari in
Current site
Google Scholar
PubMed
Close
 DVM, PhD
, and
Katherine Jenkins From the Department of Veterinary PathoBiology, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108.

Search for other papers by Katherine Jenkins in
Current site
Google Scholar
PubMed
Close

Click on author name to view affiliation information

SUMMARY

Objectives

To determine whether platelets are hyperaggregable or form platelet-neutrophil aggregates during the prodromal stages of acute laminitis of ponies.

Animals

Healthy adult ponies: 8 experimental and 6 control.

Procedures

Acute laminitis was induced by oral administration of corn starch and wood flour to 8 ponies, and indices of platelet activation were evaluated. Blood samples were collected before and at 4, 8, 12, 24, 28, and 32 hours after carbohydrate administration, and PCV, total plasma protein concentration, platelet count, activated clotting time, whole blood recalcification time, spontaneous platelet aggregation, ex vivo platelet aggregation responses, and platelet-neutrophil aggregates were determined. When lameness was first detected, ponies were euthanatized and arteriography and histologic examination of hooves were performed.

Results

Carbohydrate overload was associated with hyperaggregability of platelets throughout the prodromal stages of laminitis and increased numbers of platelet-neutrophil aggregates. Reduction of blood supply to affected hooves was variable, and blood clots were found in 6 of 11 laminitis-affected hooves.

Conclusions

Platelets were hyperaggregable throughout the prodromal stages of carbohydrate-induced laminitis and formed platelet-neutrophil aggregates. Platelet-neutrophil aggregates may initiate or contribute to development of acute laminitis.

Clinical Relevance

Anti-platelet therapy may be useful for treatment of acute alimentary laminitis in horses. (Am J Vet Res 1997;58:1376–1380)

SUMMARY

Objectives

To determine whether platelets are hyperaggregable or form platelet-neutrophil aggregates during the prodromal stages of acute laminitis of ponies.

Animals

Healthy adult ponies: 8 experimental and 6 control.

Procedures

Acute laminitis was induced by oral administration of corn starch and wood flour to 8 ponies, and indices of platelet activation were evaluated. Blood samples were collected before and at 4, 8, 12, 24, 28, and 32 hours after carbohydrate administration, and PCV, total plasma protein concentration, platelet count, activated clotting time, whole blood recalcification time, spontaneous platelet aggregation, ex vivo platelet aggregation responses, and platelet-neutrophil aggregates were determined. When lameness was first detected, ponies were euthanatized and arteriography and histologic examination of hooves were performed.

Results

Carbohydrate overload was associated with hyperaggregability of platelets throughout the prodromal stages of laminitis and increased numbers of platelet-neutrophil aggregates. Reduction of blood supply to affected hooves was variable, and blood clots were found in 6 of 11 laminitis-affected hooves.

Conclusions

Platelets were hyperaggregable throughout the prodromal stages of carbohydrate-induced laminitis and formed platelet-neutrophil aggregates. Platelet-neutrophil aggregates may initiate or contribute to development of acute laminitis.

Clinical Relevance

Anti-platelet therapy may be useful for treatment of acute alimentary laminitis in horses. (Am J Vet Res 1997;58:1376–1380)

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 54 54 15
PDF Downloads 37 37 6
Advertisement