Plasminogen-125I responses in dogs to a single injection of urokinase and typhoid vaccine and to vascular injury

Abstract

A B S T R A C T In vivo plasminogen responses to various stimuli were studied. Plasminogen-'251 was prepared and used first for metabolic studies of plasminogen in control dogs.

Physicochemical and Biological Properties of Human and Canine Plasmins

“…This was also true in vitro when [jI]plasminogen was incubated with urokinase at 380C for 5 min (1)(2)(3). The ['"I]plasmin generated both in vivo and in vitro was detected and quantified by the method devised in this laboratory (1)(2)(3), using disc gel electrophoresis (4).…”

“…A single kind of ['"I]plasmin is generated from ['I]-plasminogen in vivo when urokinase is injected into dogs (1)(2)(3). This was also true in vitro when [jI]plasminogen was incubated with urokinase at 380C for 5 min (1)(2)(3).…”

“…Canine plasminogen was prepared by the method previously reported (1), and human plasminogen was prepared by a minor modification of our. previous method (1). About 1 liter of citra-ted human plasma obtained from the blood bank was proved to be free of Australia antigen and antibody by the hemagglutination assay methods (5).…”

“…About 1 liter of citra-ted human plasma obtained from the blood bank was proved to be free of Australia antigen and antibody by the hemagglutination assay methods (5). The modifications were in the use of centrifugation at 5,000 rpm for 5 min and 40%o (NH4)2SO4 saturation instead of what was described previously (1). The difference between canine and human plasminogens in DEAE cellulose chromatography was that the former appears in the effluent volumes of 200-300 ml (1), whereas the latter appears in the effluent volumes of about 600400 ml.…”

“…They were not 100% pure by disc electrophoresis (4), but this provided a rapid and convenient method for preparing about 90% pure peaks 1 and 2 and about 95% pure peak three plasmins. The three plasmins were preserved in 50% glycerol in 0.05 M sodium phosphate buffer (pH 7.0), which were then analyzed with respect to their extinction coefficients and specific activity as described previously (1). The plasmin activity was measured by the caseinolytic method (7) and by the fibrinolytic method of Moser and Frey (8).…”