The effects of pentoxifylline infusion on plasma 6-keto-prostaglandin F1 alpha and ex vivo endotoxin-induced tumour necrosis factor activity in horses.

This study investigates the effects of pentoxifylline infusion on plasma concentrations of 6-keto-prostaglandin F1 alpha and how it could suppress endotoxin-induced tumour necrosis factor activity in horses.

Experimental Procedure

• Pentoxifylline, at a dose of 7.5 mg/kg, was intravenously injected into eight healthy horses, followed by an infusion at a rate of 1.5 mg/kg/h over a period of 3 hours.
• The horses’ clinical parameters were monitored and blood samples were collected over a 24-hour period.
• The plasma was then separated from the blood samples and the concentrations of pentoxifylline, its metabolite I, and 6-keto-prostaglandin F1 alpha were measured.
• Additionally, heparinized whole blood was incubated ex-vivo with Escherichia coli endotoxin before the determination of plasma tumour necrosis factor activity.

Findings

• The highest concentrations of pentoxifylline and its metabolite I occurred 15 minutes after the initial injection. The plasma concentration levels were 9.2 +/- 1.4 and 7.8 +/- 4.3 micrograms/mL respectively.
• The half-life of the pentoxifylline elimination process was 1.44 hours and the volume of distribution was 0.94 L/kg.
• The average plasma concentration of 6-keto-prostaglandin F1 alpha increased over time, showing a significant increase 30 minutes after the bolus administration.
• Additionally, the ex-vivo plasma endotoxin-induced tumour necrosis factor activity significantly decreased at the 1.5 hour and 3 hour marks of the infusion period.

Conclusion

• The results suggest that the infusion of pentoxifylline can increase the presence of 6-keto-prostaglandin F1 alpha and considerly suppress the activity of endotoxin-induced tumour necrosis factor in horses during the infusion period.