Abstract：ObjectiveThe mortality and incidence of delayed encephalopathy after acute carbon monoxide poisoning (DEACMP) rats were compared by intraperitoneal injection and inhalation.Methods180-230g male wistar rats were randomly divided into intraperitoneal injection group(n＝80), inhalation group (n＝240) and control group 1 and control group 2 (n＝8,respectively). According to 150ml/kg, DEACMP animal models were made by intraperitoneal injection in 150ml/kg dose of carbon monoxide in intraperitoneal injection group. According to different doses of CO, rats in inhalation group were divided into low dose group (1000ppm, n＝80), middle dose group (3000ppm, n＝80) and high dose group (4000ppm, n＝80). Rats in blank control group were injected with equal volume of air (control group 1) or were put in the cabin filled with air (control group 2). The concentration of carboxy hemoglobin (HbCO) in the tail blood was monitored and the incidence of DEACMP was detected by water maze test. ResultsThe mortality of 3000ppm group, 4000ppm group and intraperitoneal injection group were 37.5% (30/80), 61.3% (49/80) and 40.0% (32/80), respectively. The mortality in 3000ppm group was lower than that in 4000ppm group, with statistical difference (χ2＝9.03,P＝0.003), but there was no significant difference between intraperitoneal group and 3000ppm group (χ2＝0.11,P＝0.746). The incidence of DEACMP in 3000ppm, 4000ppm and intraperitoneal injection group was 40.0% (20/50), 41.9% (13/31) and 14.6% (7/48), respectively. The incidence of DEACMP in 3000ppm group was higher than that in intraperitoneal injection group (χ2＝7.93,P＝0.005), but there was no significant difference between 4000ppm group and 3000ppm group (χ2＝0.03,P＝0.860). Conclusion3000ppm inhalation poisoning is the best way to build DEACMP animal model.
