Study on the Ristocetin-precipitated fibrinogen and Ristocetin induced platelet aggregation
| Autor: | Masaaki Konishi, Seiichiro Kawai, Humito Kato, Katsura Kusunose, Sotoharu Yamada, Masami Kato, Makoto Kuto, Yuya Izuchi, Katsumi Deguchi, Hisashi Beppu |
|---|---|
| Rok vydání: | 1977 |
| Předmět: |
congenital
hereditary and neonatal diseases and abnormalities medicine.medical_specialty biology Afibrinogenemia Chemistry Ristocetin-induced platelet aggregation General Medicine Fibrinogen In vitro chemistry.chemical_compound Endocrinology Von Willebrand factor hemic and lymphatic diseases Internal medicine Immunology biology.protein medicine Platelet Receptor Ristocetin circulatory and respiratory physiology medicine.drug |
| Zdroj: | Blood & Vessel. 8:423-428 |
| ISSN: | 1884-2372 0386-9717 |
| Popis: | Howard arid Firkin have described that the ristocetin induced platelet aggregation (RIPA) is defective in von Willebrand's disease (vWd), but is normal in afibrinogenemia. They also noted that ristocetin causes precipitation of fibrinogen. A key factor of RIPA seems to be the factor lacking in vWd, not fibrinogen, since a plasma level of fibrinogen is normal in vWd. Although RIPA is vWd defective at usual final concentration (F. C.) (1mg/ml), it occurs at high F. C. (2, 3mg/ml).On the other hand, platelets in our two patients with afibrinogenemia aggregated at usual F. C. of ristocetin, but the aggregation strength and curve pattern were differed from those in normal. The RIPA of these patients were normalized with fibrinogen in vitro and vivo.Rabbit anti-fibrinogen serum completely inhibited RIPA in citrated normal PRP when it was added 3min. before ristocetin. (F. C. 1.0, 2.0, 3.0mg/ml)These findings led us to study the interaction between fibrinogen and ristocetin.In this study it was confirmed that ristocetin causes precipitation of fibrinogen as reported already.In addition it was found that FVIII-antigen level decreased in the supernant of PRP or PPP centrifused at 10, 000g. 30min. after adding various F. C. of ristocetin.Ristocetin precipitated fibrinogen (RPF) was prepared by adding high F. C. of ristocetin to placheck and/or platelet suspended plasma.On phase contrast and electron microscopic observation of RPF, placheck and/or platelet were seen in RPF clump as if they were entrapped within clump.Hence, we have assumed that at the early stage in RIPA, von Willebrand factor and receptor on the surface membrane of platelet play a chief role in usual F. C., while RPF clump play an important role in high F. C. of ristocetin (2, 3mg/ml).Also in RIPA at usual F. C. fibrinogen seems to be concerned in an aggregation strength and curve pattern. |
| Databáze: | OpenAIRE |
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