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Definition of platelet-derived histamine-releasing factor and histaminergic receptors modulating platelet aggregation

P F Mannaioni1, A Pistelli, F Gambassi

  • 1Department of Preclinical and Clinical Pharmacology, University of Florence, Italy.

International Archives of Allergy and Applied Immunology
|January 1, 1991
PubMed

Endogenous and exogenous free radical scavengers significantly decrease mast cell histamine release induced by coincubation with resting, activated platelets or with platelet-derived supernatant. Histamine and pyridylethylamine dose-dependently enhance platelet aggregation; the effect is potentiated by ranitidine and blocked by mepyramine. Histamine increases also cytosolic calcium concentration in platelets stimulated with thrombin, and binding sites for [3H]-mepyramine are present on platelet membranes.

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