Koistinaho J, Roivainen R, Yang G
Department of Public Health, University of Tampere, Finland.
Mol Cell Endocrinol. 1990 May 28;71(1):R1-6. doi: 10.1016/0303-7207(90)90078-m.
The circadian variation in the expression of c-fos protein(s) in the adrenal cortex of adult rats was investigated immunocytochemically. The animals were maintained in standard laboratory facilities with a 12:12 h light:dark schedule (07.00-19.00 h) until sacrificed. The number of c-fos immunoreactive (c-fos IR) cells was statistically constant in the zona fasciculata and zona reticulata at 20.00 h and 24.00 h, and 04.00 h, but was decreased to 52% at 08.00 h and to 18% at 12.00 h, respectively, when compared to the 24.00 h value. At 16.00 h, the number of c-fos IR cells was increased again to 63% of the 24.00 h value. In the zona granulosa c-fos IR was observed only at 20.00 h and 24.00 h. Administration of dexamethasone, a potent inhibitor of ACTH release, significantly reduced the number of c-fos IR cells. As the circadian rhythm of c-fos expression in the adrenal cortex correlates to that reported for ACTH secretion from the pituitary, the results suggest that c-fos gene is involved in mediating physiological ACTH-induced responses in the adrenal cortical cells.
采用免疫细胞化学方法研究成年大鼠肾上腺皮质中c-fos蛋白表达的昼夜变化。将动物饲养在标准实验室环境中，光照周期为12小时光照：12小时黑暗（07:00-19:00），直至处死。在束状带和网状带中，c-fos免疫反应性（c-fos IR）细胞数量在20:00、24:00和04:00时在统计学上保持恒定，但与24:00时的值相比，在08:00时降至52%，在12:00时降至18%。在16:00时，c-fos IR细胞数量再次增加至24:00时值的63%。在颗粒带中，仅在20:00和24:00时观察到c-fos IR。给予地塞米松（一种促肾上腺皮质激素释放的强效抑制剂）可显著减少c-fos IR细胞数量。由于肾上腺皮质中c-fos表达的昼夜节律与垂体促肾上腺皮质激素分泌的昼夜节律相关，结果表明c-fos基因参与介导肾上腺皮质细胞中生理促肾上腺皮质激素诱导的反应。
