Na⁺/H⁺-Austausch und Thrombozytenaktivierung

Zusammenfassung

Die Stimulation von Thrombozyten mit Thrombin führt zur Erhöhung von pH_i. Diese Alkalisierung des Zytoplasmas wird durch die Aktivität eines Na⁺/H⁺-Austauschers in der Plasmamembran bewirkt. Vermutlich katalysiert die Proteinkinase C die Phosphorylierung dieses Transportsystems. Die Erhöhung von pH_i ist eine wichtige Voraussetzung für die IP₃-induzierte Ca²⁺-Freisetzung aus intrazellulären Speichern und damit unerläßlich für die Thrombozytenaktivierung (Abb. 5).

Gefördert dureh die Deutsche Forschungsgemeinschaft (Sehe 46/5-1 und Sehe 46/5-2)

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