Effect of liver cirrhosis on potency of propofol for sedation in rats

Objective To investigate the effect of liver cirrhosis on the potency of propofol for sedation in rats. Methods Fifty-eight male SD rats, aged 10-12 weeks, weighing 180-220 g, were randomly divided into 3 groups: control group (group C, n = 18), mild liver cirrhosis group (group M1, n =20) and severe liver cirrhosis group (group M2, n = 20). The model of liver cirrhosis was established using four factors described by Chen et al. After successful establishment of the model, propofol was injected intravenously. The dose of propofol was determined by up-and-down sequential method for loss of righting reflex. The dose of propofol was 5.912 mg/kg in the first rat and the ratio of the doses between the two consecutive rats was 0.85. ED50 of propofol was calculated using up-and-down sequential method. Results ED50 of propofol was significantly lower in group M1 and M2 than in group C and in group M2 than in group M1 ( P ＜ 0.05 or 0.01 ). Conclusion The liver cirrhosis can enhance the potency of propofol for sedation in rats. Key words: Cirrhosis; Propofol; Dose-response relationship,drug