RESUMO
A melanoma cell line (Bowes) was found to produce plasminogen activator even on its growing phase, and the rate of plasminogen activator production was rather constant. The production of plasminogen activator was proportional to the cell number. Morphologically, no specific features for plasminogen activator production were seen. Plasminogen activator was observed in the lysate of this cell line only when the cell number was large. The extracellular plasminogen activator activity was higher than the intracellular plasminogen activator activity, suggesting the existence of a secretion mechanism for the plasminogen activator.
Assuntos
Melanoma/enzimologia , Ativadores de Plasminogênio/biossíntese , Contagem de Células , Linhagem Celular , Células Cultivadas/ultraestrutura , Técnicas de Cultura , Microscopia de Contraste de FaseRESUMO
The role of plasminogen activator in ovulation was investigated using the inhibitor, trans-aminomethylcyclohexane carboxylic acid (t-AMCHA). In the regular cycle rat, the plasminogen activator activity of the follicles increased from the diestrus to the estrus phase. In the latter phase, a proteolytic enzyme which was not inhibited by t-AMCHA appeared. After ovulation, the plasminogen activator activity decreased. When ovulation was induced in immature rats by pregnant mare serum gonadotrophin and human chorionic gonadotrophin, remarkable fibrinolytic activity appeared in the ovaries immediately before ovulation. When t-AMCHA was given in the ovulation-induced rats, the fibrinolytic activity of the ovaries was suppressed, the number of ovulated ova decreased and the timing of ovulation was delayed. When t-AMCHA solution was given to rats in the proestrus phase, ovulation was almost completely suppressed, but aprotinin solution exerted no effect on ovulation. These results suggest that plasminogen activator is a key enzyme in ovulation, and that the chain reaction from plasminogen activator to proteolytic enzyme (including collagenase) is of greater importance than that of plasminogen activator to plasmin.
Assuntos
Ácidos Cicloexanocarboxílicos/farmacologia , Ovulação , Ativadores de Plasminogênio/fisiologia , Ácido Tranexâmico/farmacologia , Animais , Gonadotropina Coriônica/farmacologia , Feminino , Fibrinólise/efeitos dos fármacos , Gonadotropinas Equinas/farmacologia , Folículo Ovariano/fisiologia , Ovulação/efeitos dos fármacos , Indução da Ovulação , Ativadores de Plasminogênio/antagonistas & inibidores , Inativadores de Plasminogênio , Ratos , Ratos EndogâmicosRESUMO
The role of plasminogen activator in ovulation was investigated using the inhibitor, trans-aminomethylcyclohexane carboxylic acid (t-AMCHA). In the regular cycle rat, the plasminogen activator activity of the follicles increased from the diestrus to the estrus phase. In the latter phase, a proteolytic enzyme which was not inhibited by t-AMCHA appeared. After ovulation, the plasminogen activator activity decreased. When ovulation was induced in immature rats by pregnant mare serum gonadotrophin and human chorionic gonadotrophin, remarkable fibrinolytic activity appeared in the ovaries immediately before ovulation. When t-AMCHA was given in the ovulation-induced rats, the fibrinolytic activity of the ovaries was suppressed, the number of ovulated ova decreased and the timing of ovulation was delayed. When t-AMCHA solution was given to rats in the proestrus phase, ovulation was almost completely suppressed, but aprotinin solution exerted no effect on ovulation. These results suggest that plasminogen activator is a key enzyme in ovulation, and that the chain reaction from plasminogen activator to proteolytic enzyme (including collagenase) is of greater importance than that of plasminogen activator to plasmin.
RESUMO
A melanoma cell line (Bowes) was found to produce plasminogen activator even on its growing phase, and the rate of plasminogen activator production was rather constant. The production of plasminogen activator was proportional to the cell number. Morphologically, no specific features for plasminogen activator production were seen. Plasminogen activator was observed in the lysate of this cell line only when the cell number was large. The extracellular plasminogen activator activity was higher than the intracellular plasminogen activator activity, suggesting the existence of a secretion mechanism for the plasminogen activator.
RESUMO
The effect of low molecular weight dextran sulphate (DS) (molecular weight 3,900) on plasminogen activation by urokinase was investigated. When human plasma containing urokinase (100 IU/ml) was diluted with DS solution and acidified to pH 4, marked splitting activity of the substrate D-Val-Leu-Lys-pNA, which is a specific substrate for plasmin, appeared. Further, the precipitate obtained after centrifugation of diluted and acidified plasma exhibited remarkable substrate splitting activity. These results indicate that activation of plasminogen to plasmin by urokinase was enhanced by the low molecular weight dextran sulphate.
Assuntos
Dextranos/farmacologia , Fibrinolisina/metabolismo , Oligopeptídeos/farmacologia , Centrifugação , Sulfato de Dextrana , Fibrinólise/efeitos dos fármacos , Humanos , Concentração de Íons de HidrogênioRESUMO
The effect of low molecular weight dextran sulphate (DS) (molecular weight 3,900) on plasminogen activation by urokinase was investigated. When human plasma containing urokinase (100 IU/ml) was diluted with DS solution and acidified to pH 4, marked splitting activity of the substrate D-Val-Leu-Lys-pNA, which is a specific substrate for plasmin, appeared. Further, the precipitate obtained after centrifugation of diluted and acidified plasma exhibited remarkable substrate splitting activity. These results indicate that activation of plasminogen to plasmin by urokinase was enhanced by the low molecular weight dextran sulphate.
RESUMO
The effect of low molecular weight dextran sulphate (DS) (molecular weight 3,900) on plasminogen activation by urokinase was investigated. When human plasma containing urokinase (100 IU/ml) was diluted with DS solution and acidified to pH 4, marked splitting activity of the substrate D-Val-Leu-Lys-pNA, which is a specific substrate for plasmin, appeared. Further, the precipitate obtained after centrifugation of diluted and acidified plasma exhibited remarkable substrate splitting activity. These results indicate that activation of plasminogen to plasmin by urokinase was enhanced by the low molecular weight dextran sulphate.
RESUMO
Using the capsule implantation method, the relationship between the intracapsular fluid pressure (IFP) and fibrinolytic activity of the intracapsular fluid was examined in subcutaneous and intramuscular capsules. When IFP was positive, the sterility test was positive (indicating infection), the fibrinolytic activity was enhanced, and the response of IFP to volume change or hypertonic solutions was poor. On the other hand, when IFP was negative, the sterility test was negative, the fibrinolytic activity was weak, and the response of IFP to volume change or hypertonic solutions was good. Also, the more negative the IFP, the weaker was the fibrinolytic activity in the intracapsular fluid (r = 0.60, p less than 0.01). The ratio of the intracapsular fluid fibrinolytic activity to the plasma fibrinolytic activity showed a good correlation to the intracapsular fluid pressure (r = 0.68, p less than 0.01). When the fibrinolytic activity was activated by injection of streptokinase and human plasma, the IFP showed a tendency to increase. These results suggest that the fibrinolytic system plays some role in the maintenance of local fluid balance.
Assuntos
Ação Capilar , Implantes de Medicamento , Espaço Extracelular , Fibrinólise , Pressão , Animais , Cápsulas , Cães , Solução Salina HipertônicaRESUMO
Using the capsule implantation method, the relationship between the intracapsular fluid pressure (IFP) and fibrinolytic activity of the intracapsular fluid was examined in subcutaneous and intramuscular capsules. When IFP was positive, the sterility test was positive (indicating infection), the fibrinolytic activity was enhanced, and the response of IFP to volume change or hypertonic solutions was poor. On the other hand, when IFP was negative, the sterility test was negative, the fibrinolytic activity was weak, and the response of IFP to volume change or hypertonic solutions was good. Also, the more negative the IFP, the weaker was the fibrinolytic activity in the intracapsular fluid (r = 0.60, p less than 0.01). The ratio of the intracapsular fluid fibrinolytic activity to the plasma fibrinolytic activity showed a good correlation to the intracapsular fluid pressure (r = 0.68, p less than 0.01). When the fibrinolytic activity was activated by injection of streptokinase and human plasma, the IFP showed a tendency to increase. These results suggest that the fibrinolytic system plays some role in the maintenance of local fluid balance.
RESUMO
Using the capsule implantation method, the relationship between the intracapsular fluid pressure (IFP) and fibrinolytic activity of the intracapsular fluid was examined in subcutaneous and intramuscular capsules. When IFP was positive, the sterility test was positive (indicating infection), the fibrinolytic activity was enhanced, and the response of IFP to volume change or hypertonic solutions was poor. On the other hand, when IFP was negative, the sterility test was negative, the fibrinolytic activity was weak, and the response of IFP to volume change or hypertonic solutions was good. Also, the more negative the IFP, the weaker was the fibrinolytic activity in the intracapsular fluid (r = 0.60, p less than 0.01). The ratio of the intracapsular fluid fibrinolytic activity to the plasma fibrinolytic activity showed a good correlation to the intracapsular fluid pressure (r = 0.68, p less than 0.01). When the fibrinolytic activity was activated by injection of streptokinase and human plasma, the IFP showed a tendency to increase. These results suggest that the fibrinolytic system plays some role in the maintenance of local fluid balance.