热暴露兔血浆内毒素含量的动态变化

Dynamic Changes of LPS Concentrations in Plasma of Rabbits Exposed to Heat

在环境温度42.0±0.3℃、湿球温度35.0±0.3℃、相对湿度60％条件下,测定了22只麻醉热应激兔的全身动脉血浆内毒素(LPS)浓度。当动物肛温从40.0℃升高到43.0℃时,短、中、长组兔的血浆LPS浓度分别由开始的0.124、0.132和0.129ng/ml升高到0.147、0.171和0.201ng/ml(P<0.05);动物死亡前各组则分别升到0.189、0.251和0.299ng/ml(P<0.05)。在肛温42.8℃至休克前这段时间,3组动物的平均心率分别为367、367、328次/min,平均动脉压为11.33、11.33和11.86KPa,呼吸频率为196、226和223次/min,经统计学处理,相差均不显著。本研究表明,动物血浆中LPS的含量升高与热暴露时间有关,而动物生理反应之改变则与血浆中高浓度的LPS水平有关。为此认为,LPS在中暑的病理生理学过程中可能具有一定作用,抗LPS抗体等在中暑防治中的应用可能是有益的。

Lipopolysaccharide (LPS) concentrations in systemic arterial plasma were determined in 22 anesthetised rabbits heat-stressed by an environmental temperature of 42.0 ± 0.3 ℃, Twb of 35.0 ± 0. 313 and 60 % relative humidity. The mean plasma LPS concentration in three groups of Ⅰ, Ⅱ and Ⅲ rabbits increased initially from 0.124,0.132 and 0.129ng/ml to 0.147,0.171 and 0.201ng/ml (P<0.05) respectively as the rectal temperature (Tre) increased from 40.0 to 43.0℃ and reached 0.189,0.251 and 0.299ng/ml (P<0.05) just prior to death respectively. During Tre 42.813-prior to shock, the heart rate(HR), mean arterial pressure(MAP) and respiratory rate (R) in three groups of I, II and III are respectively 367, 367 and 328b/min (NS), 11.33,11. 33 and 11. 86kpa(NS), 196,226 and 223 T/min(NS). This study shows that increase of the LPS concentration in plasma is relative to the heat exposure time and the change of physiological response for animals is relative to the LPS level of high concentration in plasma. We conclude that LPS may have a role in heat stroke pathophysiology. If so, then the use of anti-LPS antibodies and so on maybe expected to be beneficial.