Thrombin enhances opsonized zymosan-induced chemiluminescence of neutrophils.
We examined the effects of alpha-thrombin (the native enzyme) on neutrophil activation as assessed by the measurement of chemiluminescence. alpha-Thrombin in physiological concentrations (10(-9)-10(-8)M) did not induce neutrophil chemiluminescence. However, when neutrophils were coincubated with opsonized zymosan and alpha-thrombin, the chemiluminescence response to opsonized zymosan was enhanced in a concentration-dependent manner. The neutrophil chemiluminescence responses to opsonized zymosan and to opsonized zymosan plus alpha-thrombin were dependent on the generation of oxygen-derived free radicals since the chemiluminescence was inhibited by superoxide dismutase. The results indicate that thrombin per se does not induce neutrophil chemiluminescence. However, thrombin enhances the chemiluminescence response to opsonized zymosan suggesting an interaction between thrombin and complement receptors in inducing neutrophil activation. The chemiluminescence response to thrombin and opsonized zymosan is the result of oxygen-derived free radicals.
Chan
K L
KL
Department of Physiology, Albany Medical College of Union University, New York 12208.
Bizios
R
R
Malik
A B
AB
D000818:Animals; D001386:Azides / Q000494:pharmacology; D066298:In Vitro Techniques; D007202:Indicators and Reagents; D008163:Luminescent Measurements; D009504:Neutrophils / Q000187:drug effects*; D012756:Sheep; D019810:Sodium Azide; D013482:Superoxide Dismutase / Q000494:pharmacology; D013917:Thrombin / Q000494:pharmacology*; D015054:Zymosan / Q000494:pharmacology*
D001386:Azides; D007202:Indicators and Reagents; D015054:Zymosan; D019810:Sodium Azide; D013482:Superoxide Dismutase; D013917:Thrombin