Carrageenin-induced thrombosis in rats and mice: a model for testing antithrombotic substances?

Among different carrageenins, kappa-carrageenans were found to be thrombogenic, whereas lambda-carrageenins were inactive in this respect, although the latter substances exerted a stronger edemogenic activity. Kappa-carrageenin (Sigma) was the most potent thrombogen. As the consequence of thrombosis tail infarction became visible some minutes after i.v. administration, but it was delayed for about 3 hours after the i.p. route and for about 6 hours after subplantar injection. Infarction frequency as well as extent of infarction was inhibited by heparin, cyproheptadine, phentolamine and dibenamine. Other substances like aspirin and dipyridamole showed no or only weak effects. Advantages of the carrageenin-induced thrombosis model in rats and mice are: (i) simple induction in small laboratory animals, (ii) easy observation and quantification all the time without killing the animals, and (iii) possible external testing of antithrombotic agents by applying substances on the tail.