Blood clotting: the function of electrolytes and of calcium

Abstract

Expts. are described which indicate that the activity of oxalate, citrate and fluoride ions in preventing coagulation is complex and is due not only to their ability to depress the Ca ion concn. of blood, but also to their ionic charge. The concns. of Ca, Mg and Ba ions needed for the coagulation of plasma containing various concns. of salts were measured. These measurements indicate that human plasma will not coagulate if the ionic strength is less than 0.01 or more than 0.5. The concn. of alkaline earth elements required for coagulation was found to vary with ionic strength, Ca concn. as low as 0.08 m[image] causing coagulation in plasma of ionic strength 0.03. The function of Ca in coagulation is discussed. It is suggested that it is concerned with the maintenance of an electrolyte balance suitable for the interaction of the plasma colloids.