急性热应激对大鼠肺细胞膜磷脂代谢及膜流动性的影响

EFFECT OF ACUTE HEAT STRESS ON THE CONTENTS OF PHOSPHOLIPIDS AND THE FLUIDITY OF CELL MEMBRANE IN RAT LUNG

使用高效液相色谱法测定了正常健康雄性大鼠经急性热应激致肛温达42℃后,肺细胞膜中磷脂酰丝氨酸(PS),磷脂酰胆碱(PC)的变化,同时用荧光探剂标记红细胞和肺组织细胞膜制剂,采用偏振荧光法测定了膜流动性的改变。结果表明,正常大鼠的PS和PC分别为425.1±68.1μg/g湿重和53.5±9.7mg/g湿重,肛温达42℃持续15min时,两者明显减低,分别为224.3±51.3μg/g湿重和26.5±5.5mg/g湿重。热应激大鼠置于室温下恢复4h后,两者又都回到正常水平。热应激后,大鼠红细胞膜及肺组织细胞膜的流动性明显降低。表明膜磷脂含量的改变对膜流动性有明显的影响。

The changes in the contents of phosphatidylserine (PS) and phosphatidylcholine (PC) in lung cell membrane of rats suffered from acute heat stress were investigated with HPLC. The membrane fluidity of the red blood cells and the lung cells from the heat-stressed rats was examined. The results showed that the contents of PS and PC in normal rats were 425.1 ±68.1μg/g wet w. and 53.5 ± 9.7mg / g wet w. respectively, whereas those in the heat-stressed rats whose rectal temperature was increased to 42℃ and maintained for 15 minutes were reduced to 224.3±51.3μg/g wet w. and 26.5 ± 5.5mg / g wet w. respectively. The membrane fluidity of RBC and lung cells was also decreased in heat-stressed rats as compared with normal control. When the heat-stressed rats recovered at room temperature for 4h, normal level of PS, PC and membrane fluidity were demonstrated. The changes observed may be related to the activation of phospholipase A2.