Skórzewska Anna, Bidziński Andrzej, Lehner Małgorzata, Turzyńska Danuta, Sobolewska Alicja, Hamed Adam, Szyndler Janusz, Maciejak Piotr, Plaznik Adam
Department of Neurochemistry, Institute of Psychiatry and Neurology, 9 Sobieskiego Street, 02-957 Warsaw, Poland.
Horm Behav. 2007 Sep;52(3):317-25. doi: 10.1016/j.yhbeh.2007.05.007. Epub 2007 May 18.
The effects of acute pretreatment of rats with corticosterone (5 and 20 mg/kg, s.c.) on emotional behavior, expression of c-Fos protein in brain structures, and serum concentration of corticosterone were studied to model the short-term glucocorticoid-dependent changes in brain functions. Corticosterone was administered 90 min before training of a conditioned fear reaction (a freezing response), and behavioral, hormonal and immunocytochemical effects were examined 1 day later, on the test day. Pretreatment of rats with corticosterone significantly attenuated the freezing reaction in the conditioned fear test. The effect of the corticosterone was accompanied by a selective enhancement of the aversive context-induced c-Fos expression in some brain structures: the parvocellular and magnocellular neurons of the paraventricular hypothalamic nucleus (pPVN and mPVN), the medial amygdala nucleus (MeA), and the cingulate cortex, area 1 (Cg1), as well as an increase in the concentration of aversive context-induced endogenous serum glucocorticoid, 1.5 h and 10 min after the test session, respectively. It is suggested that the behavioral effects of acute pretreatment of rats with corticosterone could be due to changes in the mnemonic processes in the brain, inhibition of brain corticotropin releasing factor (CRF) synthesis, or stimulation of GABA-A receptor modulating neurosteroids synthesis. It is hypothesized that the enhanced activity of Cg1, MeA, pPVN, and mPVN, and the hypothalamic-pituitary-adrenal axis with concomitant increased serum glucocorticoid concentration, might serve to facilitate active coping behavior in a threatening situation.
研究了用皮质酮（5和20mg/kg，皮下注射）对大鼠进行急性预处理对情绪行为、脑结构中c-Fos蛋白表达以及血清皮质酮浓度的影响，以模拟脑功能中短期糖皮质激素依赖性变化。在训练条件性恐惧反应（僵住反应）前90分钟给予皮质酮，并在训练后1天（测试日）检查行为、激素和免疫细胞化学效应。用皮质酮预处理大鼠可显著减弱条件性恐惧测试中的僵住反应。皮质酮的作用伴随着在一些脑结构中厌恶情境诱导的c-Fos表达的选择性增强：下丘脑室旁核的小细胞和大细胞神经元（pPVN和mPVN）、杏仁核内侧核（MeA）和扣带回皮质1区（Cg1），以及在测试 session 后1.5小时和10分钟时，厌恶情境诱导的内源性血清糖皮质激素浓度增加。提示用皮质酮对大鼠进行急性预处理的行为效应可能是由于脑内记忆过程的改变、脑促肾上腺皮质激素释放因子（CRF）合成的抑制或GABA-A受体调节神经甾体合成的刺激。据推测，Cg1、MeA、pPVN和mPVN的活性增强以及下丘脑-垂体-肾上腺轴与血清糖皮质激素浓度的同时增加，可能有助于在威胁情境中促进主动应对行为。
