Platelet cothromboplastin: a platelet factor(s) related to the blood clotting mechanisms^[*)]

Summary

Bovine Platelets contain a factor(s) that greatly enhances the capacity of lung extract thromboplastin to conver purified prothrombin to biothrombin. It also may function with Russell’s viper venom in the activation of prothrombin The activity is destroyed below pH 4 or above pH 11 or at temperatures above 52° C. Concentrates of the activity have been obtained in a fraction of platelets that consists predominately of carbohydrate and protein.

^*) This investigation was supported by a research grant H-2026 (c) form the National Heart Institute, National Institutes of Health. Funds for Research Fellowships in Physiology were provided by Parke, Davis and Company.

^**) Fellow of the Presbyterian Church Mission Board of the United States of America. Home address: Department of Physiology, Severence Union Medical College, Seoul, Korea. By coincidence a previous paper on this subject was also by Lee, Johnson and Seegers; however, in that instance the first author was Chen-Yuan Lee of Formosa.

• References

• 1 Lee C. Y, Johnson S. A, and Seegers W. H. Clotting of blood with Russell’s viper venom. J. Mich. med. Soc. 54: 801 1955;
• 2 Seegers W. H, Loomis E. C, and Vandenbelt J. M. Preparation of prothrombin products. Isolation of prothrombin and its properties. Arch. Biochem. 6: 85 1945;
• 3 Seegers W. H. The purification of prothrombin. Ree. Chem. Prog. 13: 143 1953;
• 4 Ware A. G, and Seegers W. H. Studies on prothrombin: Purification, inactivation with thrombin, and activation with thromboplastin and calcium. J. biol. Chem. 174: 565 1948;
• 5 Schneider C. L, Claxton E. B, Hughes C. H, and Johnson S. A. Bovine platelets in large quantities, properties, and activities concerned with hemostasis. Amer. J. Physiol. 179: 236 1954;
• 6 Seegers W. H, and Smith H. P. Factors which influence the activity of purified thrombin. Amer. J. Physiol. 137: 348 1942;
• 7 Ware A. G, and Seegers W. H. Two-stage procedure for the quantitative determination of prothrombin concentration. Amer. J. clin. Path. 19: 471 1949;
• 8 Ware A. G, Fahey J. L, and Seegers W. H. Platelet extracts, fibrin formation and interaction of purified prothrombin and thromboplastin. Amer. J. Physiol. 154: 140 1948;
• 9 Dreywood R. Qualitative test for carbohydrate material. Ind. Engng. Chem. Anal. Ed. 18: 499 1946;
• 10 Carter J. R. Amperometric Determination of disulfides in intact proteins. Science 120: 895 1954;
• 11 Milton R. F, and Water W. A. Methods of quantitative microanalysis. Arnold; London: 1949
• 12 Seegers W. H, Alkjaersig N, and Johnson S. A. Formation of auto-prothrombin I in solutions containing purified prothrombin and purified platelet factor 3. Amer. J. Physiol. 181: 589 1955;
• 13 Macfarlane R. G, Trevan J. W, and Attwood A. M. P. Participation of a fat-soluble substance in coagulation of the blood. J. Physiol. (London) 99: 7 1941;
• 14 Leathes J. B, and Mellanby J. The action of lecithin on the thrombokinase of deboia venom and of brain extracts. J. Physiol. (London) 96: 39 1939;
• 15 Rapaport S. L, Aas K, and Owren P. A. The clotting action of Russell’s viper venom. Blood 9: 1185 1954;
• 16 Hjort P, Rapaport S. I, and Owren P. A. A simple specific one-stage prothrombin assay using Russell’s viper venom in cephalin suspension. J. Lab. clin. Med. 46: 89 1955;
• 17 Seegers W. H, Johnson S. A, and Penner J. A. Quantitative concepts related to prothrombin and autoprothrombin I activity. Can. J. Biochem. Physiol. 34: 887 1956;