Sánchez P, Torres J M, Gavete P, Ortega E
Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Granada, Granada, Spain.
Neurochem Int. 2008 Feb;52(3):426-31. doi: 10.1016/j.neuint.2007.07.019. Epub 2007 Aug 3.
The metabolite of progesterone, allopregnanolone, is among the most potent known ligands of the gamma-aminobutyric acid receptor complex (GABA(A)-R) in the central nervous system. This neuroactive steroid is markedly increased in an animal model of acute stress. Allopregnanolone is synthesized from progesterone by steroidogenic enzymes 5alpha-reductase (5alpha-R) and 3alpha-hydroxysteroid dehydrogenase (3alpha-HSD), with the former being the rate-limiting enzyme in this reaction sequence. In this paper, a quantitative RT-PCR method coupled to laser-induced fluorescence capillary electrophoresis (LIF-CE) and Western blot were used to measure both mRNA and protein levels of 5alpha-R type 1 (5alpha-R1) and 5alpha-R type 2 (5alpha-R2) isozymes in prefrontal cortex of male rats after acute swim stress situations. Our results demonstrate that both 5alpha-R isozymes are significantly higher in prefrontal cortex of male rats after acute swim stress in comparison with control rats. These data may open up a new research line that could improve our understanding of the role of 5alpha-R isozymes in processes that accompany stress situations.
孕酮的代谢产物别孕烯醇酮是已知的中枢神经系统中γ-氨基丁酸受体复合物（GABA(A)-R）最有效的配体之一。这种神经活性类固醇在急性应激动物模型中显著增加。别孕烯醇酮由甾体生成酶5α-还原酶（5α-R）和3α-羟基类固醇脱氢酶（3α-HSD）从孕酮合成，前者是该反应序列中的限速酶。在本文中，采用定量逆转录聚合酶链反应（RT-PCR）方法结合激光诱导荧光毛细管电泳（LIF-CE）和蛋白质免疫印迹法，来测定急性游泳应激情况下雄性大鼠前额叶皮质中5α-R1和5α-R2两种同工酶的mRNA和蛋白质水平。我们的结果表明，与对照大鼠相比，急性游泳应激后雄性大鼠前额叶皮质中两种5α-R同工酶的水平均显著升高。这些数据可能开辟一条新的研究路线，有助于我们更好地理解5α-R同工酶在应激相关过程中的作用。
