Disseminated intravascular coagulation in rats was induced by intravenous infusion of thrombin for 30 min. The glomerular filtration rate was measured as the clearance of polyethylene glycol 1000. The fibrin deposition in organs was quantitated by a method using previous injection of <sup>125</sup>I-labelled fibrinogen. Administration of the β-adrenergic blocking agent, propranolol, prevented the decrease in glomerular filtration rate after infusion of thrombin. This result could be explained by an observed partial redistribution of the fibrin from the kidneys to the lungs.