Vascular reactivity in endotoxin shock: effect of lidocaine or indomethacin pretreatment

The effects of indomethacin or lidocaine pretreatment on vascular reactivity of endotoxin-shocked rats were examined, using the isolated rat aorta preparation. Contractility was examined in a randomized dose-response manner to both norepinephrine and the prostaglandin endoperoxide analog U-46619. One hour after endotoxin in vivo, there was maximal decrease in contractility to both U-46619 and to norepinephrine. Neither lidocaine nor indomethacin alone significantly altered the log dose-response curve to either agonist. Neither lidocaine nor indomethacin prior to endotoxin altered the log dose-response curve when compared to endotoxin treatment alone. These data indicate that the mechanism of protection afforded by both indomethacin and lidocaine in endotoxin shock models may be independent of the effect of endotoxin on vascular reactivity.