The Inhibitory Effect of Sialic Acid on Fibrinolysis

Summary

The inhibitory effect of N-acetylneuraminic acid and glycolyl neuramaminic acids on the hydrolysis of ⁵¹Cr tagged casein by plasmin and α-chymotrypsin has been demonstrated. N,O-diacetylneuraminic acid was ineffective. The inhibitory effect was increased by an increase in ionic strength of the reaction mixture. The two active sialic acids also inhibited the fibrinolytic action of human plasmin on heated and unheated bovine fibrin plates. The greater inhibition noted on heated plates may indicate a primary effect on plasmin rather than on activators of plasmin. The inhibitory effects of N-acetyl neuraminic acid appeared to be potentiated by normal serum inhibitors. Sialic acid did not influence the conversion of fibrin monomer to polymer.

N-acetylneuraminic acid may play an important role in preserving the integrity of fibrin deposits in the body.

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