Effect of Nigella sativa on blood hemostatic function in rats.

Nigella sativa (NS) is consumed excessively in Saudi Arabia and Gulf Countries but few studies were conducted on its effects on hemostasis. The effects of NS on blood coagulation and some liver function tests of normal adult male albino rats were investigated. Equivalent (180mg NS/kg rat/day), half, double, and triple doses of NS powdered seeds incorporated in a flour dough were administered for 1, 2, and 4 weeks. Controls received plain flour dough. At the end of each feeding period, platelet count, prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), levels of fibrinogen, antithrombin III (AT III), and albumin, and activity levels aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were determined. As compared to the control, the equivalent dose of NS induced significant hyperfibrinogenemia (14%) after 4 weeks while the double dose induced significant transient PT prolongation (7.8%) and TT reduction (13%) after 2 weeks and the triple dose induced significant transient APTT reduction (16%), and TT reduction (13%) after 1 week. There was an increase in the albumin level and ALT activity paralleling that of fibrinogen. No changes were noticed in platelet count, AT III level, and AST activity. In conclusion, NS within the doses used seems to induce transient changes in the coagulation activity of rats.