Naunyn-Schmiedeberg's Archives of Pharmacology

, Volume 278, Issue 3, pp 261–269 | Cite as

Effect of lidoflazine (R 7904) on uptake and release of serotonin by human platelets in vitro

  • F. F. De Clerck
  • R. S. Reneman


At low concentrations in vitro (starting at 5×10−8 M), lidoflazine reduces the velocity of serotonin uptake by human platelets suspended in Tyrodealbumin. Inhibition is of a non-competitive type and is not enhanced by prolonged compound incubation.

At higher concentrations (starting at 1.6×10−6 M) lidoflazine causes release of radioactive serotonin from platelets. The extent of release is dependent on concentration, duration of incubation and temperature and is not reduced by calcium chelation or papaverine pre-treatment. Similar but less pronounced effects on uptake and release reactions occur with dipyridamole. The possible mode of action of lidoflazine on platelet storage of serotonin is discussed.

Key words

Platelets Serotonin Storage Lidoflazine Dipyridamole 


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Copyright information

© Springer-Verlag 1973

Authors and Affiliations

  • F. F. De Clerck
    • 1
    • 2
  • R. S. Reneman
    • 1
    • 2
  1. 1.Cardiovascular Research DepartmentJanssen Pharmaceutica, Research LaboratoriesBeerseBelgium
  2. 2.Janssen Research FoundationBeerseBelgium

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