Study of Blood Coagulation Parameters in Mlac:WR Rat Produced by the National Laboratory Animal Center
Keywords:
Mlac:WR rat, Blood coagulation, Prothrombin time (PT), Activated partial thromboplastin time (APTT), Coagulation factorsAbstract
Wistar rats have been used as animal models for testing the toxicity of pharmacological products. Blood coagulation tests are used to detect abnormalities in the blood clotting mechanism. Currently, the Wistar rats produced by the National Laboratory Animal Center have not been studied for their blood coagulation values. Therefore, this study measured the blood coagulation parameters, prothrombin time (PT) and activated partial thromboplastin time (APTT), in Mlac:WR rats using a SYSMEX CA-660 automated coagulation analyzer. The results showed that both sex and age significantly affected the mean PT and APTT values at the 95% confidence level (p < 0.05). In terms of stability, plasma samples stored at -20°C for 2 weeks prior to analysis tended to have shorter PT values but significantly prolonged APTT values (p < 0.001). Furthermore, Mlac:WR rats that received sterile water via oral gavage for 90 consecutive days showed no significant differences in coagulation values compared to the non-oral gavage group, except for the male APTT value, which significantly decreased in the oral gavage group (p < 0.001). This study demonstrates that sex, age, and variations in the daily routines of experimental animals, as well as pre-analytical sample storage conditions, can influence blood coagulation parameters in Wistar rats.
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