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Turbidimetry on Human Washed Platelets: The Effect of the Pannexin1-inhibitor Brilliant Blue FCF on Collagen-induced Aggregation
Published on: April 6, 2017
The first- and second-generation antipsychotic drugs affect ADP-induced platelet aggregation
Anna Dietrich-Muszalska1, Jolanta Rabe-Jablonska, Pawel Nowak
1Department of Affective and Psychotic Disorders, Medical University of Lodz, Lodz, Poland. tzn_lodz@post.pl
Summary
Second-generation antipsychotics, clozapine and olanzapine, significantly inhibit ADP-induced platelet aggregation in vitro. This finding may explain reduced thrombotic risks in schizophrenia patients treated with these drugs.
Area of Science:
- Pharmacology
- Cardiovascular Medicine
- Neuroscience
Background:
- Blood platelets are crucial for hemostasis; hyperaggregability increases thrombosis and cardiovascular disease risk.
- Schizophrenic patients on antipsychotics face higher mortality and thrombotic complications.
- Antipsychotic effects on platelet function are not fully understood.
Purpose of the Study:
- To investigate and compare the in vitro effects of second-generation antipsychotics (clozapine, risperidone, olanzapine) and a first-generation antipsychotic (haloperidol) on ADP-induced platelet aggregation.
Main Methods:
- Platelet-rich plasma was obtained from 25 healthy volunteers.
- Platelet aggregation induced by 10 µM ADP was measured using a Chrono-log aggregometer.
- Plasma was preincubated with clozapine, risperidone, olanzapine, or haloperidol before ADP addition.
Main Results:
- All tested antipsychotics inhibited ADP-induced platelet aggregation in vitro.
- Clozapine and olanzapine demonstrated significant reductions in platelet aggregability.
- Clozapine inhibited aggregation by 21% (P=3.7x10⁻⁶), and olanzapine by 18% (P=2.8x10⁻⁴) compared to controls.
Conclusions:
- Antipsychotics, particularly clozapine and olanzapine, reduce blood platelet response to ADP.
- This antiaggregatory effect may partially mitigate prothrombotic events in schizophrenic patients.
- Further research is needed to elucidate the antiaggregatory mechanisms of antipsychotics.
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