フィブリンゲル形成の速度論的研究 -フィブリノペプタイドA, B加水分解の意義- Kinetic study on the formation of fibrin gels ; A role of hydrolysis of fibrinopeptides A and B from fibrinogen on gel structure
Fibrinogen, treated by thrombin, leads to des-AABB-fibrinogen, while Reptilase-treated fibrinogen leads to des-AA-fibrinogen, where fibrinopeptides A and B are abbreviated as A and B, respectively. Both des-AABB-fibrinogen and des-AA-fibrinogen automatically form gels, abbreviated as fnT and fnR, repectively. Their gel structures, however, are difficult to be distinguished by the electron microscopy. For the purpose to compare the gel formation of both des-AABB-fibrinogen and des-AA-fibrinogen, the kinetic change of the absolute values of complex elasticity,|G*|, in the fibrinogen-fibrin (F-fn) conversion to fnT and fnR was investigated in experimental conditions similar to the physiological ones. Moreover, our rheological study was carried out in conditions such as almost the same turbidimetrical changes were observed between F-fnT and F-fnR in the early stage.<BR>There was observed the most remarkable turbidimetrical change subsequently to an induction period. Then,|G*|was found out to increase rapidly, and approached gradually to a maximum value|G*|<SUB>max</SUB>. In fnT,|G*|<SUB>max</SUB> was much higher than that of fnR. The density of cross-linking in fnT was estimated to be higher by 2.25 times than that in fnR from the plots of|G*|against frequency in quasi-equilibrium state. In addition,|G*|<SUB>max</SUB> of fnR was the same as that of fnT, formed in a half concentration of fibrinogen, indicating that the hydrolysis of fibrinopeptide A against the hydrololysis of both fibrinopeptides A and B contributes to the gel structure approximately in a half ratio. In the logarithmic plots of|G*|against (t-t<SUB>0</SUB>), the values for fnT and fnR were overlayed on a curve in the early stage. That is, the structure of fnT appears to be similar to that of fnR in this stage, taking into consideration the more selective hydrolysis of fibrinopeptide A than fibrinopeptide B from fibrinogen by thrombin in physiological conditions.
- 日本バイオレオロジー学会誌(B&R) = Journal of Japanese Society of Biorheology
日本バイオレオロジー学会誌(B&R) = Journal of Japanese Society of Biorheology 13(1), 28-34, 1999-03-31