Effect of propranolol, barbiturate anesthesia and splenectomy on factor VIII:C and plasminogen activator release...

After the injection of DDAVP in 39 non-anaesthetized dogs (0.4 micrograms/kg) factor VIII:C activity rose to 145% of baseline values (p less than 0.0001) and the fibrinolytic potential of euglobulin precipitate rose to 196% (p less than 0.0001). The injection of DDAVP was repeated three times in each dog of a group of good responder animals at weekly intervals, but after: A) Pentobarbital anesthesia (30 mg/kg)--the increase of factor VIII:C was reduced from 164% to 116% (n = 11; p less than 0.0005) and the increase in fibrinolytic activity was reduced from 270% to 192% (n = 11; p less than 0.05). B) Injection of propranolol (1 mg/kg)--the increase of factor VIII:C was reduced from 167% to 110% (n = 13; p less than 0.0005) and there was no significant decrease of fibrinolytic activity (n = 13; n.s.) C) Splenectomy--the increase of factor VIII:C was reduced from 166% to 122% (n = 10; p less than 0.0005) and fibrinolytic activity was not significantly changed from 196% to 256% (n = 9; n.s.). There were no statistically significant differences in the increases of factor VIII:C and fibrinolytic potential of euglobulin precipitate after repeating only the injection of DDAVP three times in the same animal at weekly intervals (n = 5; n.s.). We conclude that the increases in factor VIII:C and fibrinolytic activities observed after DDAVP infusion in the dog are due to different mechanisms of action.(ABSTRACT TRUNCATED AT 250 WORDS)