We investigated the effect of 16,16-dimethyl prostaglandin E-2 indomethacin and Ginkgo biloba extract on the survival in two experimental sepsis models in rats due to administration of 1 x 10(7) cfn and 1 x 10(9) cfu Escherichia coli. Animals in each model were then randomly divided (10/group) into four groups, administered saline, indomethacin, G. biloba extract and prostaglandin E-2 respectively. When compared, there was no significant difference in the survival period between the two sepsis models (P>0.05). The best survival rate was observed in the PGE(2)-administered animals in the first major model(P<0.05). Indomethacin appeared not to decrease the mortality rates. There was no significant difference in PGE(2) levels between two sepsis models (P>0.05). Our results suggest that elevated prostaglandin E-2 levels following major trauma are not responsible for the postinjury increased susceptibility to infectious complications. Our observations should also discourage aggressive use of cyclo-oxygenase inhibitors for protection against infectious complications after major trauma.