title: Fish protein stimulated the fibrinolysis in rats.
abstract: OBJECTIVE
  We hypothesized that fish protein affects blood coagulation and/or fibrinolysis, and compared the activity and amounts of factors involved in blood coagulation and fibrinolysis in rats fed the fish protein, which was treated to remove water-soluble and ethanol-soluble elements, from sardine (sardine protein).
  
  
  METHODS
  In the first experiment, rats were fed for 21 days an AIN-93G-based control diet, and diets in which the casein of the control diet was exchanged for sardine protein at 5, 10 and 20% levels. In the second experiment, rats were fed an AIN-93G control diet and diets containing 5% fish oil, 10% sardine protein or both (5% fish oil + 10% sardine protein) for 21 days. At the end of the experiments, blood coagulation time, hemostatic parameters and fibrinolysis parameters were measured.
  
  
  RESULTS
  The activated partial thromboplastin time (APTT), which is an assay for blood coagulation time in the intrinsic blood coagulation pathway, of rats fed the 20% sardine protein diet was significantly prolonged compared to that of rats fed the control diet. The prolonged APTT by dietary sardine protein was due to a significant decrease of the activities of plasma blood coagulation factors VIII, IX, XI and XII. On the other hand, dietary sardine protein significantly increased the activity of tissue-type plasminogen activator, and the amount of plasma plasmin-alpha(2)-plasmin inhibitor complex, which are markers of activated plasmin. Moreover, we observed that the 20% sardine protein diet increased the amount of plasma D-dimer, which is a degraded product of the fibrin polymer by plasmin. In the second experiment, the APTT and PT of rats fed the F diet were prolonged compared to those of rats fed the control diet, however the concentration and amount of fibrinolytic parameters in the plasma were almost the same as those of rats fed the control diet. In contrast, the F+S diet not only prolonged APTT and PT, but also increased the concentration and amount of fibrinolytic parameters in plasma.
  
  
  CONCLUSIONS
  We consider that the beneficial effects to health and amelioration of cardiovascular and cerebrovascular diseases by fish consumption are caused by a combination of the suppressing effect on blood coagulation of n-3 polyunsaturated fatty acids and the promoting effect on fibrinolysis of fish protein.
authors.affiliation: Laboratory of Functional Biochemistry, Biochemistry and Food Technology Division, Organization of National Research Institute of Fisheries Science, Fisheries Research Agency, Yokohama, Japan. murama@affrc.go.jp
authors.forename: Masakazu
authors.initials: M
authors.lastname: Murata
authors.forename: Yoko
authors.initials: Y
authors.lastname: Sano
authors.forename: Seiko
authors.initials: S
authors.lastname: Bannai
authors.forename: Kenji
authors.initials: K
authors.lastname: Ishihara
authors.forename: Ryoji
authors.initials: R
authors.lastname: Matsushima
authors.forename: Motoharu
authors.initials: M
authors.lastname: Uchida
mesh_terms: D000818:Animals; D001777:Blood Coagulation / Q000187:drug effects; D001779:Blood Coagulation Factors; D001780:Blood Coagulation Tests; D004305:Dose-Response Relationship, Drug; D005342:Fibrinolysis / Q000187:drug effects*; D029941:Fish Proteins / Q000494:pharmacology*; D008297:Male; D010314:Partial Thromboplastin Time; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D001779:Blood Coagulation Factors; D029941:Fish Proteins