June 1979

pH-Induced Platelet Ultrastructural AlterationsA Possible Mechanism for Impaired Platelet Aggregation

Author Affiliations

From the Departments of Medicine B (Dr Djaldetti), Surgery A (Dr Chaimoff), and the Electron Microscopy Unit, Hasharon Hospital, Petah-Tiqva, Israel, and the Tel Aviv University Medical School, Tel Aviv, Israel (Mesdames Fishman and Bessler).

Arch Surg. 1979;114(6):707-710. doi:10.1001/archsurg.1979.01370300061009

• After the observation that lavages with alkaline solutions exert a beneficial effect on the bleeding tendency and increase platelet aggregation in patients with intragastric hemorrhage, studies were undertaken to find a relationship between changes of pH and platelet morphology. Transmission and scanning electron microscopy showed that at a pH lower than 7.4, normal human platelets change their internal structure as well as their shape, becoming spheres deprived of pseudopodia. On the other hand, a pH higher than 7.4 induces transformation of platelet internal organelles similar to that caused by thrombin. At an alkaline pH, the platelets develop multiple pseudopodia that facilitate their attachment to each other. These findings may explain the increased platelet aggregation in alkaline medium demonstrated in one of our previous works.

(Arch Surg 114:707-710, 1979)