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PubMed · 16308184

Does meta-chlorophenylpiperazine (mCPP) activate human platelets?

A E Frampton·J C H Andrews·A Parfitt·I A Jagroop·D P Mikhailidis·J A Henry
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Abstract

mCPP (meta-chlorophenylpiperazine), an agonist at serotonin (5-hydroxytryptamine, 5-HT) 5-HT2 receptors, has been used as a probe of serotonergic function. We assessed its effect on platelet activation by measuring median platelet volume (MPV), the Sonoclot (SCT) pattern and plasma and intraplatelet serotonin. (a) In vitro study: MPV was measured (n = 7) using a high-resolution channelyzer: Saline (median and range (5.23 fl; 5.10-6.18) vs. mCPP (5.36; 5.10-6.44) P = 0.03; ADP (5.42; 5.29-6.44) vs. ADP + mCPP (5.67; 5.42-6.63) P = 0.02; mCPP (5.36; 5.10-6.44) vs. ADP + mCPP (5.67; 5.42-6.63) P = 0.02. Therefore, mCPP increases the MPV and enhances the effect of ADP. (b) In vivo study: The SCT time to inflection (TI) and time to peak (TP) were measured following the oral administration of mCPP (0.5 mg/kg) or aspirin (300 mg) (n = 10). Ingestion of mCPP significantly shortened TI and TP indicating platelet activation. TI: 0 h (mean +/- SD: 10.2 +/- 2.0 min) vs. 6 h (9.3 +/- 1.5) P = 0.03; TP: 0 h (31.9 +/- 7.6) vs. 6 h (23.1 +/- 2.9) P = 0.01. Aspirin had no effect on TI or TP. There were no significant changes in plasma and intraplatelet 5-HT. It is concluded that mCPP activates human platelets via 5-HT receptors.

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Adenosine DiphosphateBlood Coagulation TestsBlood PlateletsHumansIn Vitro TechniquesPiperazinesPlatelet ActivationSerotoninSerotonin 5-HT2 Receptor AgonistsTime FactorsComparative StudyJournal Article

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A E Frampton, J C H Andrews, A Parfitt, I A Jagroop, D P Mikhailidis, J A Henry. 2006. Does meta-chlorophenylpiperazine (mCPP) activate human platelets?. https://doi.org/10.1080/09537100500129490

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