Acute death and oxidative damage induced by acute phosgene inhalation of different concentration-time (Ct) in rats

ObjectiveTo investigate acute death and oxidative damage of ratinduced by acute phosgene inhalation of different concentration-time(Ct).MethodsSixty male SD rats were randomly divided into six groups:one control group and five phosgene exposure groups of different Ct(unit:ml·min)of 3×3,15×1,7.5×2,5×3 and 10×3,respectively.After being exposed to phosgene for 24 hours,the fatality rate of each group was calculated,and the expr ession of nuclear factor (NF-JB)in the liver was detected.The control group and all rats survival groups after exposure to phosgene were defined as the oxidative damage obser vation groups.The lung wet/dry weight ratio,the content of malondialdehyde(MDA)and the activity of superoxide dismutase(SOD)in the serum and liver were examined.ResultsThe fatality rate was 0/10 in control group,3×3 group and 15×1 group,and 4/10 in 7.5×2 group and 5×3 group,and 10/10 in 10×3 group,respectively.NF-JB was expressed in all groups but the contr ol group,and was most obvious in 15×1 gr oup.The control group,3×3 group and 15×1 group were elected as the oxidative stress observation groups.The lung wet/dry weight ratio of 3 ml×3 min group and 15×1 group showed no difference compared with the control group(P>0.05);The content of MDA in liver tissue,the activity of SOD in liver tissue and blood serum of 15×1 group were much higher than that of control group(P<0.05).Neither the MDAn or SOD of 3×3 group showed difference compared with control group(P>0.05).ConclusionWhen the Ct was same,the intoxation of phosgene positively correlated with the exposure time,indicating thatin the process of acute death induced by phosgene inhalation,the contribution of exposure time was more fatal than that of exposure concentration;In nonlethal condition,the oxidative damage and inflammatory reaction induced by phosgene were closely related to the phosgene's concentration.