Modification of Platelet Function by Radical Species Produced During Irradiation of Oxygenated Water

Summary

Gel-filtered platelets in neutral, oxygen-containing solutions irradiated to a dose of 10 krad with γ-rays display a significant inhibition of ADP-induced aggregation. Though the superoxide anion radical (O^- ₂) and H₂O₂ are generated in water irradiated under these conditions, only catalase, but not superoxide dismutase (SOD), conveyed protection against this inhibition of platelet function. When the platelets are in the presence of 10^-3 M sodium formate, which converts the majority of the radical species formed to O^- ₂, inhibition of aggregation was again observed. Under these circumstances, the addition of catalase significantly decreased this inhibition, whereas the addition of SOD was without effect.

In order to separate the platelet-inhibition effects of the radical species generated in the medium from a direct effect of irradiation on platelet components, relatively stable quantities of O^- ₂. were produced in alkaline solutions and reacted with gel-filtered platelets. Again, an inhibition of ADP-induced aggregation was observed. This inhibition was not significantly altered by the addition of SOD, but was abolished by the addition of catalase, either with or without SOD.

Our observation would indicate that O^- ₂.is without direct effect on platelet function, but serves as the precursor of H₂O₂, which can inhibit platelet reactions.

Keywords

γ-irradiation - Platelet aggregation - Platelet lysisa - O^- ₂ - H₂O₂

• References

• 1 Iyer GY N, Islam MF, Quastel JH. Biochemical aspects of phagocytosis. Nature (Lond) 1961; 192: 525-541
• 2 Babior BM, Kipnes RS, Cumutte JT. Biological defense mechanisms. The production by leukocytes of superoxide, a potential bactericidal agent. J Clin Invest 1973; 52: 741-744
• 3 Klebanoff SJ. Antimicrobial mechanisms in neutrophilic polymorphonuclear leukocytes. Sem Hemat 1975; 12: 117-142
• 4 Babior BM. Oxygen-dependent microbial killing by phagocytes. New Eng J Med 1978; 298 659-668 721-725
• 5 Barnhart MI. Cellular fibrinogen. Thromb Diath Haemorrh 1964; 11 (Suppl. 13) 157-165
• 6 Henry RL. Leukocytes and thrombosis. Thromb Diath Haemorrh 1965; 13: 35-46
• 7 Jørgenson L, Rowsell HC, Hovig T, Mustard JF. Resolution and organization of platelet rich mural thrombi in carotid arteries of swine. Am J Path 1967; 51: 681-719
• 8 Canoso RT, Rodvien R, Scoon K, Levine PH. Hydrogen peroxide and platelet function. Blood 1974; 43: 645-656
• 9 Rodvien R, Lindon JN, Levine PH. Physiology and ultrastructure of the blood platelet following exposure to hydrogen peroxide. Brit J Haem 1976; 33: 19-26
• 10 Levine PH, Weinger RS, Simon J, Scoon KL, Krinsky NI. Leukocyte-platelet interaction. Release of hydrogen peroxide by granulocytes as a modulator of platelet reactions. J Clin Invest 1976; 57: 955-962
• 11 Stuart MJ, Holmsen H. Hydrogen peroxide, an inhibitor of platelet function: Effect on adenine nucleotide metabolism and the release action. Am J Hemat 1977; 2: 53-63
• 12 Handin RI, Carabin R, Boxer GJ. Enhancement of platelet function by superoxide anion. J Clin Invest 1977; 59: 959-965
• 13 Koufos A, Sagone Jr AL. Effects of oxidant stress on the hexose monophosphate shunt pathway of platelets. Blood 1980; 55: 835-840
• 14 Levine PH, Sladdin DG, Krinsky NI. Superoxide, xanthine oxidase and platelet reactions. Further studies on mechanisms by which oxidants influence platelets. In Press Throm Haemostas;
• 15 Spinks JW T, Woods RJ. An Introduction to Radiation Chemistry. 2. nd edn, Wiley-Interscience; New York: 1976
• 16 Jarrett RD, Halliday JW. Dosimetry in support of wholesomeness studies. J Food Proc Pres 1979; 3: 145-175
• 17 Van Gelder BF, Slater EC. The extinction coefficient of cytochrome c. Biochim Biophys Acta 1962; 58: 593-595
• 18 Lages B, Scrutton MC, Holmsen H. Secretion by gel-filtered human platelets: Response of platelet Ca²⁺, Mg²⁺, and K⁺ to secretory agents. J Lab Clin Med 1977; 90: 873-882
• 19 Clark RA, Klebanoff SJ. Myeloperoxidase-mediated platelet release reaction. J Clin Invest 1979; 63: 177-183
• 20 Simic MG, Taub IA. Mechanisms of inter- and intra-molecular electron transfer in cytochromes. Farad Disc Chem Soc 1977; 63: 270-278
• 21 Bielski BHJ. Reevaluation of the spectral and kinetic properties of HO₂ and O^- ₂ free radicals. Photochem Photobio 1978; 28: 645-649
• 22 Beers Jr RF, Sizer IW. A spectrophotometric method for measuring the breakdown of hydrogen peroxide by catalase. J Biol Chem 1952; 195: 133-140
• 23 McCord JM, Fridovich I. Superoxide dismutase. An enzymatic function for erythrocuprein (hemocuprein). J Biol Chem 1969; 244: 6049-6055
• 24 Bielski BH J, Allen AO. Mechanism of the disproportionation of superoxide radicals. J Phys Chem 1977; 81: 1048-1050
• 25 Hart EJ. γ-Ray-induced oxidation of aqueous formic acid-oxygen solutions. Effect of pH. J A Chem Soc 1954; 76: 4198-4201
• 26 Tauber AI, Babior BM. Evidence for hydroxyl radical production by human neutrophils. J Clin Invest 1977; 60: 374-379
• 27 Weiss SJ, Rustagi PK, LoBuglio AF. Human granulocyte generation of hydroxyl radical. J Exp Med 1978; 147: 316-323