Comparación de la activación y la cinética de laplasmina bufalina con la humana / Ativação e cinética comparativa da plasmina bufalina e a humana / Comparative activation and kinetic of plasmin bufaline with the human one

El plasminógeno es el zimógeno de la plasmina, enzima activada a nivel fisiológico por el activadortisular del plasminógeno y la urokinasa, la plasmina es la enzima encargada de disolver el coágulosanguíneo. En este estudio se compararon la plasmina humana con la bufalina en su forma de activación dezimógeno a enzima y en la afinidad hacia el sustrato cromogénico. Los plasminógenos fueron purificadospor el mismo método de cromatografías de afinidad y cambio iónico. De igual manera las activaciones sehicieron utilizando urokinasa humana en ambos casos. La plasmina bufalina demostró mayor activacióny afinidad (1.35mM) que la plasmina humana (2.16 mM), siendo la bufalina 1.5 veces mas afin al sustratocromogénico que la humana. Este estudio demuestra que el método de purificación de los plasminógenospuede ser el mismo para muchas especies, se demuestra una vez más que las plasminas animales al parecerson más eficientes en la disolución del coágulo o degradación de sustratos, que la plasmina humana.Este estudio indica que la plasmina bufalina puede ser utilizada en los parámetros que se determinanclínicamente en pacientes con problemas cardiovasculares, reduciendo el tiempo de determinación de estosparámetros fibrinolíticos, que pueden dar al médico un margen de tiempo superior para actuar.

The Plasminogen is the zymogene of the Plasmin, enzyme which physiologically is activated by twodifferent enzymes, the tissue plasminogen activator and the urokinase, the plasmin is the enzyme that dissolves blood clots. In this study the human plasmin was compared to the bufaline plasmin, in theactivation from the zymogene to the enzyme form as well as in the affinity to the chromogenic substrate.The two plasminogens were purified by the same chromatographies methods: affinity and ion-exchange.Furthermore, both plasminogens were activated by human urokinase. The bufaline plasmin showed moreactivation and affinity (1.35 mM) that the human plasmin (2.16 mM), in addition, the bufaline plasmindemonstrated a 1.5 times more affinity to the chromogenic substrate that the human plasmin. This studydemonstrated that the plasminogens of several species can be purified by this method. Besides, one moretime the animal’s plasmins probably to be more efficient in the dissolution of blood clots or degradation ofsubstrates than the human plasmin. More over this study indicated that the bufaline plasmin can be usedin clinical determinations of patients with cardiovascular diseases. This also reduces the determinationtime of fibrinolytic parameters that physicians can give, having more time to take appropriate treatment.

O plasminogênio é o zymogen da plasmina, enzima ativada a nivel fisiológico pelo ativador tissulardo plasminogênio e uroquinase, plasmina é a enzima responsável de dissolver o coágulo de sanguíneo.neste estudo foi comparada a plasmina humana com a plasmina búbalina em seu modo de ativaçãode zymogen a enzima e na afinidade substrato cromogênico. Os plasminogênio foram purificados como mesmo método de cromatografia de afinidade e de troca iônica, e as ativações foram feitas usandouroquinase humana nos dois casos. A Búfalo plasmina mostrou maior ativação e afinidade (1.35 mM)que a plasmina humana (2.16 mM), sendo a bufalina 1.5 vezes mais afim ao substrato Cromogênico quea humana. Este estudo mostrou que o método de purificação do plasminogênios pode ser o mesmo paramuitas espécies, alem disso, que as plasminas animais são mais eficientes na dissolução do coáguloo degradação de substratos que a plasmina humana. Este estudo indicou que a plasmina búfalo podeser utilizada nos parâmetros determinados clínicamente em pacientes com problemas cardiovasculares,diminuindo o tempo de determinação destes parâmetros fibrinolíticos, que podem dar ao médico umintervalo de maior tempo para atuar.

The Effect of Intracisternal Urokinase for the Development of Hydrocephalus after Experimental Subarachnoid Hemorrhage

The authors has investigated the effect of intracisternal urokinase on the multihemorrhage canine model of chronic post-subarachnoid hemorrhage(SAH) hydrocephalus. Each of 16 adult mongrel dogs was assigned to one of two experimental groups. All animals received a total of 13ml of fresh unheparinized autologous blood via three cisternal injections. Eight animals were treated by intracisternal injection of 20,000 IU of Urokinase every 12 hours for 3 days, and the remaining were not treated. The changes in ventricular volumes were measured by computed tomography(CT) before and 3 months after the initial subarachnoid blood injection. To compare the changes of hydrodynamic properties in chronic phases of post-SAH hydrocephalus, the pressure-volume index(PVI) technique of bolus manipulation of cerebrospinal fluid(CSF) was used to measure the volume-buffering capacity of neural axis and the resistance to the absorption of CSF(before SAH, post-SAH 1 month, 3 months). The final ventricular volume at 3 months of control group was 4 times greater than the initial volume, but Urokinase group less than two times. The mean measured PVI values of control group and Urokinase group were 3.98+/-0.76ml(+/- standard deviation(SD)) and 4.01+/-0.82ml in baseline study, 3.09+/-0.96ml and 3.70+/-0.84ml in post-SAH 3 months. The mean resistance of CSF outflow of control group and Urokinase group were 10.30+/-2.24mm Hg/ml/min), and 10.34+/-1.98mm Hg/ml/min in baseline study. At 1 month and 3 months after SAH control group maintained high absorptive resistance(29.54+/-11.50mm Hg/ml/min, 22.43+/-3.82mm Hg/ml/min), whereas the resistances of Urokinase group were slightly increased and then returned to the original levels(16.04+/-4.87mm Hg/ml/min, 12.87+/-3.06mm Hg/ml/min). The results described in this experimental study indicated that if fibrinolysis of the subarachnoid blood clot can be achieved rapidly after SAH, the complicating chronic hydrocephalus might be prevented.