A high fat meal activates blood coagulation factor VII in rats

In humans, high fat meals cause postprandial activation of blood coagulation factor VII (FVII), but human studies have not provided definite evidence for a prothrombotic effect of dietary FVII activation. An animal model would be an attractive way to pursue this question and therefore we tested the LEW/Mol rat. We gavaged 3 mL of a fat emulsion (n = 42) or 3 mL isotonic glucose (n = 42). Blood was sampled by heart puncture 2, 4 and 6 h (n = 14/group at each time) after the fat/glucose load. Furthermore, blood was sampled from 16 untreated rats to determine the baseline levels. Triglyceride concentrations, activated FVII (FVIIa), FVII coagulant activity (FVIIc), FVII amidolytic activity (FVIIam) and thrombin-antithrombin complexes (TAT) were determined. After fat administration, triglycerides were significantly elevated at 2 h (1.29 mmol/L) and 4 h (1.37 mmol/L) compared with baseline (0.78 mmol/L), and FVIIa was significantly raised at 4 h (54 U/L) and 6 h (58 U/L) compared with baseline (29 U/L). No postprandial changes in FVIIc, FVIIam and TAT were observed. Glucose administration did not affect any variable. We conclude that the LEW/Mol rat is a promising model for use in future studies of thrombotic effects of dietary FVII activation.