Modulation of equine platelet function by diethylcarbamazine (DEC).

Area of Science:

• Pharmacology
• Hematology
• Veterinary Medicine

Background:

• Equine platelets play a crucial role in hemostasis.
• Anthelmintic drugs can have unintended effects on host physiology.
• Diethylcarbamazine (DEC) is commonly used to treat heartworm disease.

Purpose of the Study:

• To investigate the effects of diethylcarbamazine (DEC) on equine platelet function.
• To determine if DEC influences serotonin release and platelet aggregation.
• To explore the dose-dependent effects and reversibility of DEC's actions on platelets.

Main Methods:

• Equine platelets were treated with varying concentrations of diethylcarbamazine (DEC).
• Radiolabeled serotonin release was measured.
• Platelet aggregation was induced by adenosine diphosphate (ADP), collagen, arachidonic acid, and thrombin.
• The reversibility of DEC's effects was assessed by drug removal prior to agonist challenge.

Main Results:

• DEC induced a dose-dependent release of radiolabeled serotonin from equine platelets.
• DEC significantly inhibited platelet aggregation induced by ADP, collagen, and arachidonic acid in a dose-dependent manner.
• Inhibition by DEC was reversible for ADP-induced aggregation but only partially reversible for collagen and appeared irreversible for arachidonic acid.
• Thrombin-induced platelet aggregation was not affected by DEC.

Conclusions:

• Diethylcarbamazine (DEC) possesses the novel property of modulating equine platelet function, including serotonin release and aggregation inhibition.
• The mechanism of DEC's action appears to involve a reversible membrane-drug interaction for ADP and collagen, and potentially irreversible inhibition for arachidonic acid.
• These findings highlight previously unrecognized pharmacological effects of DEC on platelet physiology.