MULTIPLE EFFECTS OF A DIAMIDINE (PROPAMIDINE) ON COMPLEMENT ACTIVATION

  • 1 January 1979
    • journal article
    • research article
    • Vol. 36  (1) , 131-137
Abstract
Propamidine, one of the diamidines used against infections with babesiae, has inhibitory and enhancing effects on complement activation as assessed by immune hemolysis of sensitized sheep red cells. Utilization of complement C1 is powerfully improved and that of C3 weakly improved by propamidine, while activation and/or fixation of C4, C5 and to a lesser degree of C8 and C9 are inhibited. At low concentrations of propamidine (< 2 mM) the enhancing effects predominate and at higher concentrations the inhibitory effects predominate. Inhibition is produced, in some cases certainly, in others likely, by interference of propamidine with binding properties of complement components. None of the complement enzymes, C1s, C42 or C3bBb, was inhibited in its hydrolytic activity. The possible significance of propamidine actions is discussed.