The effect of thrombin on the oxygen consumption of washed human platelets was measured polarographically with the Clark oxygen electrode. The average basal respiratory rate was 18±1.6 (mean ±S.E.) natoms oxygen per min per 109 platelets. Thrombin (1.9 units/ml) caused a 4-13-fold increase in the rate of oxygen consumption (138±14 (mean ±S.E.) natoms oxygen per min per 109 platelets). The thrombin-stimulated increase of oxygen consumption was transient, lasting from 1 to 1.5 min before returning to the respiratory rate observed before the thrombin addition. Release of platelet constituents appeared to precede the stimulation of oxygen consumption. These results may provide a basis for explaining the discrepancy in the literature concerning the effects of thrombin on platelet respiration.
ASJC Scopus subject areas
- Cell Biology