Assay and Content of Tissue Thromboplastin in Different Organs*

Abstract

Summary1. The assay of thromboplastin in tissues in terms of units of concentration by means of the double logarithmic graph is described and discussed. The significance of comparing thromboplastin in terms of concentrations and not in terms of activities is explained.2. The concentration of thromboplastin in some human and animal organs is estimated. Great variations are encountered in concentrations. The differences are larger than is generally assumed from activity assays only. The possible role of these differences in the local repair of tissue injuries as part of the hemostatic balance is mentioned.