Effect of phosgene on apoptosis of alveolar type II cells and vascular endothelial growth factor in exposed mice / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the apoptosis of alveolar type II cells, alterations of vascular endothelial growth factor (VEGF), VEGF receptor (Flt1) in serum and lung and expression of VEGF mRNA in lung in pulmonary edema mice induced by phosgene.</p><p><b>METHODS</b>Twenty-six BALB/C mice were randomly divided into 2 groups: control group, exposed group (13 mice in each group). Mice of exposed group were intoxicated by inhalation of phosgene 11.9 mg/L for 5 minutes. Mice of control group were treated as the same way by inhalation of air. Isolation of mice alveolus type II cells 4 h after intoxication was carried out to observe their apoptosis under electron microscope. Contents of VEGF and Flt1 in lung and serum by ELISA, and expression of VEGF mRNA were determined.</p><p><b>RESULTS</b>Alveolar type II cells were identified by tannic acid staining and electron microscopy. After exposed to 11.9 mg/L of phosgene for 5 minutes, the apoptotic body in alveolus type II cells was found in exposed group. The contents of VEGF in serum and lung and Flt1 in lung of exposed mice [(134.07 +/- 120.26), (477.76 +/- 98.06), (1,2818.48 +/- 2,304.15) pg/ml] were significantly lower than those of control group [(445.57 +/- 173.30), (1,026.87 +/- 474.56), (21,976.51 +/- 7,421.01) pg/ml, P < 0.05] but the content of Flt1 in serum [(2,369.56 +/- 381.70) pg/ml] was higher than that in control group [(1,898.00 +/- 453.69) pg/ml, P < 0.05]. The expression of VEGF mRNA in pulmonary edema mice was decreased.</p><p><b>CONCLUSION</b>Phosgene can induce apoptosis of alveolar type II cells, and decrease in the content of VEGF and Flt1, and expression of VEGF mRNA in lung.</p>

Effect of acute phosgene inhalation on antioxidant enzymes, nitric oxide and nitric-oxide synthase in rats / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the effect of acute phosgene inhalation on the antioxidant enzymes, nitric oxide (NO) and nitric oxide synthase (NOS) in rats.</p><p><b>METHODS</b>Phosgene was produced by decomposing bis (trichdomethyl) carbonate in the presence of N,N-dimethyl formamide. SD rats were randomly divided into two groups: control and phosgene exposure groups. In a special experimental device with equipment modulating the gas flow, phosgene exposed rats inhaled phosgene quantitatively for five minutes. Two hours later, all the rats were sacrificed and the ratio of wet weight to dried weight of lung (WW/DW) was calculated. Peripheral blood, serum and liver were collected to examine the activities of antioxidant enzymes including glutathione S-transferase (GST), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), NOS, and NO level. The total content of proteins were also determined.</p><p><b>RESULTS</b>The WW/DW ratio of lung in phosgene exposure group was much higher than that in control group (P < 0.01). The activities of GST in serum and liver of phosgene exposure group increased significantly (P < 0.05). The activities of SOD, CAT, GSHPx and NOS in serum or blood and liver of phosgene exposure group were also increased significantly (P < 0.05). But the content of NO was significantly decreased (P < 0.01).</p><p><b>CONCLUSION</b>Acute phosgene inhalation may cause a dramatically changes of several antioxidant enzyme activities, and acute injury of liver to some extent in rats. The latter is related to reactive oxygen species. But the elevation of antioxidant enzyme activities suggests that antioxidative treatment for acute phosgene poisoning should not be considered first.</p>