高温对大鼠肝胞液糖皮质激素受体的影响

EFFECTS OF HIGH TEMPERATURE ON THE GLUCOCORTICOID RECEPTORS IN THE CYTOSOL OF RAT LIVER

用放射配基结合分析法检测体温达４２℃的大鼠肝胞液中糖皮质激素受体（ＧＲ）的最大结合容量（８ｍａｘ）和Ｋｄ值的变化；问时测定了肝脏中ｃＡＭＰ、糖原及蛋白含量的变化。结果表明，过热大鼠肝细胞ＧＲ的Ｂｍａｘ明显减少，亲和力无刚显改变；而ｃＡＭＰ含量明显增加，肝蛋白和糖原含量明显减少。热应激前预先用阿的平处理大鼠后，除肝蛋白外．上述所测指标比热应激织明显增加，但ＧＲ的Ｂｍａｘ仍低于正常值（Ｐ＜０．０１），ｃＡＭＰ水平却明显超过正常值（Ｐ＜０．０１），而蛋白和糖原含量与对照组无明显差异。

Changes of the maximal binding capacity(Bmax)and the dissociation constant(Kd)of glucocorticoid receptors in the cytosol of rat liver were measured by Radioligand Binding Assay in the heat stressed rats with rectal temperature raised to 42℃by using 45℃ circulated water as a heating source,and so were cAMP,protein and glycogen content in the liver.The result shows the Bmax of GR in the heat stressed rat liver was clearly decreased without changes of affinity while the content of cAMP apparently increased with protein and glycogen content decreased in liver.With the rats being pretreated with Quinacrine,the above indexes were obviously increased than the heat stressed group except liver protein,but the Bbax of GR is still lower than normal value(P<0.01)while the content of cAMP is more than normal value(P<0.01).The protein and glycogen content shows no remarkable difference as with the compared group.