Abstract: Objective To study the effect of sagittaria sagittifolia on expression of TN F-αmRNA in process of cadmiuminduced acute liver damage.Methods Thirty-six male Sprague-Dawley rats were randomly assigned into six groups,each of six.The rats were pretreated intragastrically with 25%,50%,75% sagittaria sagittifolia extract(2ml/100g·bw),vitamin E(50mg/100g·bw)or distilled water once daily for ten days.Twenty-four hours after the last dosing,animals were administered with CdCl₂(20μmol/kg·bw)intraperitoneally.Control animals were given distilled water only.Twenty-four hours after the intoxication,the liver MDA content,serum GPT and LDH activity were measured in each group above;the TNF-α mRNA was also semi-quantified by reverse-transcription polymerase chain reaction(RT-PCR).Results Pretreatment of rats with medium and high concentration of sagittaria sagittifolia extract could decrease liver MDA content,serum GPT and LDH activity(P<0.05),and three dose of sagittaria sagittifolia extract could also inhibit liver TNF-α mRNA levels induced by cadmium(P<0.05);However,vitamin E only decreased liver MDA content(P<0.05).Conclusion Pretreatment with sagittaria sagittifolia extract can militate cadmium-induced acute liver damage through decreasing the expression of TNF-α mRNA in the process of acute cadmium exposure.