Aggravating effect of hyperthermia on lipopolysaccharideª²mediated ALI/ARDS in rats

    LIN Xiaoª²Jing, ZOU Fei, LI Yaª²Jie, WANG Bin, HAN Xueª²Lin, HE Wenª²Jing

    1Department of Nursing, Nanfang Hospital, 2Institute of Public Hygiene and Tropic Medicine, Southern Medical University, Guangzhou 510515, China

    ¡¾Abstract¡¿ AIM: To observe the effect of hyperthermia on lipopolysaccharide (LPS)ª²mediated ALI/ARDS in rats. METHODS: Male specificª²pathogen free Wistar rats were randomly assigned to the following groups: salineª²injected normothermic control (Cª²Group), salineª²injected heat exposed (Hª²Group), LPSª²injected normothermic control (Lª²Group) and LPSª²injected heat exposed (HLª²Group). Rectal temperature (Tr) was continually monitored. Plasma levels of TNFª²¦Á and ILª²6, arterial blood gas, lung wetª²toª²dry weight ratio (W/D), and lung histological change were observed at 0, 40, 80 and 120 min. RESULTS: ¢Ù The rats in HLª²Group displayed significantly higher values of Tr (43.04¡À0.11) ¡æ compared with C/Lª²Group (P<0.01). There was no significant difference between HLª²Group and Hª²Group (P>0.05). ¢Ú Significant elevations of the peak TNFª²¦Á level (at 80 min) and ILª²6 expression were seen in HLª²Group (P<0.01). ¢Û The values of HCO3ª² and PaCO2 significantly decreased at 40 min in HLª²Group(P<0.01). At 120 min, the values of HCO3ª² and PaCO2 decreased to (10.42¡À1.06) mmol/L and (2.82¡À0.81) kPa respectively. ¢Ü Significantly increased W/D ratio and many pathological features of acute microvascular lung injury were seen in HLª²Group. CONCLUSION: Hyperthermia may aggravate ALI/ARDS in LPSª²injected rats. ......