Study on glucocorticoid receptor of brain cytosol in rats with traumatic brain edema

摘要

The high-affinity glucocorticoid binding sites（HAGS）and the low-affinity glucocor-ticoid binding sites（LAGS）with steroid specificity were demonstrated in cerebral cytosol ofrats by using the radioligand binding assay.The equilibrium dissocation constant（Kd）of HAGSand LAGS were（2.78+0.71）×10-8mol/L and（2.12±1.06）×10-6mol/L respectively as esti-mated by Scatchard and Pseudoseatchard analysis.Glucocorticoid receptors（GR）in the trau-matized（left）hemisphere cytosol were decreased more significantly than those in both the con-trol（right）hemisphere cytosol at 6 h postinjury and normal brain tissue（P0.05）,but Kd ofGR showed no significant changes.GR of liver cytosol at 6h postinjury were more markedly de-creased than normal hepatic cytosol,but Kd of GR underwent no significant changes.These da-ta demonstrate that high-dose glucocorticoid（GC）used in the treatment of traumatic brain ede-ma might maintain target-cell reactions by increasing the production of GC receptor complexesand is most likely to be mediated by LAGS.