Intravenous pentoxifylline does not affect the exercise-induced pulmonary arterial, capillary or venous hypertension in Thoroughbred horses.
Abstract: The present study was carried out to examine whether intravenously administered pentoxifylline-a phosphodiesterase inhibitor which increases red blood cell deformability and decreases blood viscosity-would attenuate the magnitude of exercise-induced pulmonary capillary hypertension in healthy, fit Thoroughbred horses and in turn, diminish the occurrence of exercise-induced pulmonary hemorrhage (EIPH). Experiments were carried out on six healthy, sound, exercise-trained Thoroughbred horses. Hemodynamic data were collected at rest, and during exercise performed at 8 and 14 m/sec on 3.5% uphill grade in the control (no medications) and the pentoxifylline (8.5 mg/kg, i.v.) experiments. The sequence of treatments was randomized for every horse and 7 days were allowed between treatments. Galloping at 14 m/sec on 3.5% uphill grade elicited maximal heart rate. In both treatments, simultaneous measurements of phasic and mean right atrial and pulmonary arterial, capillary and wedge pressures were made using catheter-tip-manometers whose signals were carefully referenced at the point of the left shoulder. In the control study, exercise resulted in progressive significant increments in heart rate, right atrial and pulmonary arterial, capillary and venous pressures; thereby, confirming that exercising Thoroughbreds develop significant pulmonary hypertension. All horses experienced exercise-induced pulmonary hemorrhage (EIPH) in the control experiments. Pentoxifylline administration to standing horses caused anxiety, tachycardia, muscular fasciculations/tremors and mild sweating, but statistically significant changes in right atrial and pulmonary arterial, capillary and venous pressures were not detected. Exercise in the pentoxifylline treatment also resulted in progressive significant increments in heart rate and right atrial as well as pulmonary vascular pressures, but these data were not statistically significantly different from those in the control study and the incidence of EIPH remained unchanged. Thus, it was concluded that i.v. pentoxifylline is ineffective in attenuating the exercise-induced pulmonary arterial, capillary and venous hypertension in healthy, fit Thoroughbred horses.
Publication Date: 2000-12-07 PubMed ID: 11107006DOI: 10.1046/j.1365-2885.2000.00262.xGoogle Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- Journal Article
- Research Support
- Non-U.S. Gov't
Summary
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
This study investigates the effect of pentoxifylline, a medication known to increase red blood cell deformability and decrease blood viscosity, on exercise-induced pulmonary hypertension in thoroughbred horses. The results indicate that pentoxifylline does not significantly alter pulmonary hypertension induced by exercise or lessen the occurrence of exercise-induced pulmonary hemorrhage in these horses.
Overview of the Research
- The research aimed to find out if pentoxifylline could reduce exercise-induced pulmonary capillary hypertension and thereby, decrease the incidence of exercise-induced pulmonary hemorrhage (EIPH) in Thoroughbred horses.
- It used six healthy, fit, and exercise-trained Thoroughbred horses as subjects. Experiments involving exercise regimens were performed, and hemodynamic data were collected both at rest and during exercise. This data was collected under two conditions: a control condition without pentoxifylline use and an experiment in which the horses received an intravenous injection of pentoxifylline.
Findings of the Research
- The intensity of the exercise regime was sufficient to induce a maximal heart rate and significant increments in right atrial and pulmonary pressures, thus verifying that exercising Thoroughbreds develop significant pulmonary hypertension.
- All horses in the control group exhibited exercise-induced pulmonary hemorrhage.
- In the experiment condition, the administration of pentoxifylline resulted in some short-term side effects in standing horses, including anxiety, increased heart rate, muscle tremors, and mild sweating. However, significant changes in right atrial and pulmonary pressures were not observed.
- Contrary to the researchers’ hypothesis, exercise in the pentoxifylline treatment group resulted in similar increases in heart rate and right atrial as well as pulmonary vascular pressures as the control group. The incidence of exercise-induced pulmonary hemorrhage also remained similar to the control condition.
Conclusion of the Research
- The results of this study indicate that intravenously administered pentoxifylline does not significantly affect the pulmonary hypertension induced by exercise in Thoroughbred horses, nor does it reduce the incidence of exercise-induced pulmonary hemorrhage in these horses.
- Therefore, the research concludes that pentoxifylline is ineffective in preventing or reducing these conditions in healthy, fit Thoroughbred horses.
Cite This Article
APA
Manohar M, Goetz TE, Rothenbaum P, Humphrey S.
(2000).
Intravenous pentoxifylline does not affect the exercise-induced pulmonary arterial, capillary or venous hypertension in Thoroughbred horses.
J Vet Pharmacol Ther, 23(5), 317-322.
https://doi.org/10.1046/j.1365-2885.2000.00262.x Publication
Researcher Affiliations
- Departments of Veterinary Biosciences and Clinical Medicine, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA. mmanohar@uiuc.edu
MeSH Terms
- Animals
- Breeding
- Female
- Hemodynamics / drug effects
- Horse Diseases / etiology
- Horse Diseases / physiopathology
- Horse Diseases / prevention & control
- Horses
- Hypertension, Pulmonary / etiology
- Hypertension, Pulmonary / prevention & control
- Hypertension, Pulmonary / veterinary
- Injections, Intravenous / veterinary
- Male
- Pentoxifylline / administration & dosage
- Pentoxifylline / therapeutic use
- Phosphodiesterase Inhibitors / administration & dosage
- Phosphodiesterase Inhibitors / therapeutic use
- Physical Conditioning, Animal / adverse effects
- Random Allocation
Citations
This article has been cited 1 times.- Hinchcliff KW, Couetil LL, Knight PK, Morley PS, Robinson NE, Sweeney CR, van Erck E. Exercise induced pulmonary hemorrhage in horses: American College of Veterinary Internal Medicine consensus statement. J Vet Intern Med 2015 May-Jun;29(3):743-58.
Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists
