Brann D W, Hendry L B, Mahesh V B
Department of Physiology and Endocrinology, Medical College of Georgia, Augusta 30912-3000.
J Steroid Biochem Mol Biol. 1995 Feb;52(2):113-33. doi: 10.1016/0960-0760(94)00160-n.
The classical genomic action of steroid hormones acting through intracellular receptors is well recognized. Within this concept of action, questions regarding the ultimate fate of the hormone and lack of a tight correlation between tissue uptake and biological activity with receptor binding remain unanswered. Evidence has accumulated that steroid hormones can exert non-classical action that is characterized by rapid effect of short duration. In most of these cases, the hormone effects occurs at the membrane level and is not associated with entry into the cell. The possible mechanisms for these non-classical actions are: (a) changes in membrane fluidity; (b) steroid hormone acting on receptors on plasma membranes; (c) steroid hormones regulating GABAA receptors on plasma membranes; and (d) activation of steroid receptors by factors such as EGF, IGF-1 and dopamine. Data have also been obtained indicating that receptor-mediated insertion of steroid hormones into DNA may take place with the steroid acting as a transcription factor. These new proposed mechanism of action of steroid hormones should not be viewed as a challenge to the classical mechanism. These diverse modes of action provide for an integrated action of hormones which may be rapid and of short duration or prolonged to address the physiological needs of the individual.
类固醇激素通过细胞内受体发挥作用的经典基因组作用已得到充分认可。在这一作用概念中，关于激素的最终命运以及组织摄取与受体结合的生物活性之间缺乏紧密相关性的问题仍未得到解答。越来越多的证据表明，类固醇激素可发挥非经典作用，其特点是作用迅速且持续时间短。在大多数此类情况下，激素作用发生在膜水平，且与进入细胞无关。这些非经典作用的可能机制包括：（a）膜流动性的变化；（b）类固醇激素作用于质膜上的受体；（c）类固醇激素调节质膜上的GABAA受体；以及（d）表皮生长因子、胰岛素样生长因子-1和多巴胺等因子激活类固醇受体。也已获得数据表明，受体介导的类固醇激素插入DNA可能发生，类固醇作为转录因子发挥作用。这些新提出的类固醇激素作用机制不应被视为对经典机制的挑战。这些不同的作用模式为激素的综合作用提供了条件，这种综合作用可能迅速且持续时间短，也可能延长以满足个体的生理需求。
