Anti-Endotoxic Effects of 3-(2'-carboxyphenyl)-4(3H)quinazolinone from Radix Isatidis

Objective To study the anti-endotoxic effect of 3-(2'-carboxyphenyl)-4(3H)-quinazolinone(CPQZN) isolated from Radix Isatidis.Methods CPQZN was extracted and isolated from Radix Isatidis and diluted into 0.5% solution.The content of endotoxin pretreated with CPQZN was quantitatively determined using Limulus test.The inhibition of endotoxin-induced fever by CPQZN was measured in rabbits.The Lipopolysaccharide(LPS)-induced death in mice pretreated with and without CPQZN was compared.Influence on the LPS-induced release of TNFα and NO in macrophages from mice was studied.Results After pretreatment with CPQZN,70.56% of endotoxin was destroyed,the endotoxin-induced fever in rabbits decreased significantly;the rate of LPS-induced death in mice dropped from 70% to 25%;the release of TNFα and NO induced by LPS in mice could be inhibited by CPQZN from Radix Isatidis and the percentage of inhibition was dependent on the dosage.Conclusion CPQZN isolated from Radix Isatidis has anti-endotoxic effect.