Progesterone Receptors and Seizure Susceptibility

黄体酮受体和癫痫易感性

• 批准号: 7671859
• 负责人: Doodipala Samba Reddy
• 金额: $ 30.88万
• 依托单位: TEXAS A&M UNIVERSITY HEALTH SCIENCE CTR
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-08-01 至 2012-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7671859
• 关键词: Address; Affect; Allopregnanolone; Anabolism; Animal Model; Anticonvulsants; Antisense Oligonucleotides; Binding; Biological Models; Brain region; Chemosensitization; Condition; DNA; Data; Development; Disease; Electrophysiology (science); Elevation; Endocrine; Epilepsy; Epileptogenesis; Equilibrium; Event; Exhibits; Finasteride; Functional disorder; GABA Receptor; Gene Expression; Gene Targeting; Genes; Genetic Models; Genomics; Goals; Hippocampus (Brain); Hormones; Intervention; Kindling (Neurology); Knock-out; Knockout Mice; Lead; Link; Mediating; Menarche; Menopause; Messenger RNA; Methodology; Modeling; Molecular; Molecular Genetics; Molecular Mechanisms of Action; Mus; Neurons; Nuclear; Outcome; Oxidoreductase; Pathway interactions; Physiological; Play; Polymerase Chain Reaction; Predisposition; Pregnancy; Principal Investigator; Progesterone; Progesterone Receptors; Property; Proteins; RU-486; Rate; Receptor Inhibition; Regulation; Research Personnel; Resistance; Reverse Transcriptase Polymerase Chain Reaction; Role; Seizures; Study Section; Techniques; Testing; Time; Transgenic Organisms; United States; Western Blotting; Wild Type Mouse; Withdrawal; Woman; dentate gyrus; granule cell; improved; innovation; knock-down; mouse model; non-genomic; novel; patch clamp; perimenstrual; postsynaptic; programs; promoter; protein expression; receptor; receptor binding; receptor expression; receptor function; relating to nervous system; research study; response; transcription factor; transmission process

DESCRIPTION (provided by applicant): Progesterone (P) plays a key role in the pathophysiology of "catamenial epilepsy", a menstrual cyclerelated seizure disorder that affects many women with epilepsy. While P's endocrine actions are mediated by the progesterone receptor (PR), P's molecular mechanism of action in seizure activity is not clearly understood. P modulates seizure activity partly through conversion to allopregnanolone, which enhances GABAA receptor function. Recently, we have made the novel discovery that PRs play a key role in seizure susceptibility. Our preliminary results underscore that PR knockout (PRKO) mice exhibit elevated seizure threshold and resistance to kindling epileptogenesis, suggesting that PRs mediate seizure susceptibility. In this application, we propose to elucidate the molecular mechanisms whereby PRs increase seizure susceptibility in the hippocampus, utilizing genetic, molecular and electrophysiological approaches. We hypothesize that progesterone's actions on seizure activity are due in part to PR regulation of hippocampal GABA^ receptor subunit expression and function that results in reduced inhibition and thereby seizure susceptibility. PR-mediated "subunit switching" leading to alterations of GABAA receptor subunit composition and functional properties are the molecular mechanism by which P controls seizure susceptibility. We propose to test this hypothesis critically utilizing 3 model systems that are well established in our lab: 1) PRKO transgenic mouse model; 2) Antisense PR inhibition in wild-type mice; and 3) RU-486 blockade of PR function in wild-type mice. The Specific Aims of this proposal are: 1) to determine whether PRs increase seizure susceptibility using the kindling model of epilepsy; and 2) to determine whether PRs are involved in P induced alterations in GABAA receptor subunit expression and channel function. Aim 1 will examine the rate of hippocampus kindling in WT and PRKO mice, with and without P and/or finasteride treatment, as an indicator of epileptogenesis. Aim 2 will assess mRNA (real-time PCR) and protein levels (Westerns blots) of GABAA receptor subunits in hippocampal subfields in WT and PRKO mice treated with P, P+finasteride, and 24 hrs after neurosteroid withdrawal. We will verify the functional importance of P induced changes in GABAA receptor subunit expression by recording GABA-gated CI" currents in acutely isolated hippocampal neurons using patch-clamp electrophysiology. Significance. The proposed study will provide novel information on the P mechanisms governing regulation of seizure susceptibility, which could lead to improved understanding of catamenial epilepsy. Relevance. Women with catamenial epilepsy have seizures clustered around their monthly cycle. However, currently the pathophysiology of this condition is not fully understood. The studies proposed in this application will help better understand the disease mechanism and thereby allow development of specific therapies for catamenial epilepsy and other conditions associated with fluctuations in progesterone levels.

描述（由申请人提供）：孕酮（P）在“ Capenenial癫痫病”的病理生理学中起关键作用，这是一种月经循环癫痫发作障碍，影响许多患有癫痫病的女性。虽然P的内分泌作用是由孕激素受体（PR）介导的，但P在癫痫发作活性中的分子作用机理尚未清楚地了解。 P通过转化为Allopregnanolone，部分调节癫痫发作活性，从而增强了GABAA受体功能。最近，我们做出了新的发现，即PRS在癫痫发作中起关键作用。我们的初步结果强调了PR敲除（PRKO）小鼠表现出升高的癫痫发作阈值和对发射癫痫发生的抗性，这表明PR介导了癫痫发作的敏感性。在此应用中，我们建议阐明PRS通过遗传，分子和电生理方法提高海马中癫痫发作易感性的分子机制。我们假设孕酮对癫痫发作活性的作用部分归因于海马GABA受体亚基表达和功能，从而导致抑制作用降低，从而降低抑制性。 PR介导的“亚基转换”导致GABAA受体亚基组成和功能特性的改变是P控制癫痫发作易感性的分子机制。我们建议在实验室中良好建立的3个模型系统进行严格的测试：1）PRKO转基因小鼠模型； 2）野生型小鼠的反义PR抑制； 3）RU-486野生型小鼠中PR功能的阻断。该提案的具体目的是：1）确定PR使用癫痫的点燃模型是否会增加癫痫发作的敏感性； 2）确定PRS是否参与P诱导的GABAA受体亚基表达和通道功能的改变。 AIM 1将检查WT和PRKO小鼠中海马点燃的速率，有和没有P和/或非雄胺治疗，作为癫痫发生的指标。 AIM 2将评估WT中海马子场中GABAA受体亚基的mRNA（实时PCR）和蛋白质水平（西部印迹）和用P，P+丁那烷基治疗的PRKO小鼠和神经类固醇后24小时的PRKO小鼠。我们将通过使用斑块钳电生理学记录急性分离的海马神经元中的gaba受体ci电流来验证P诱导的GABAA受体亚基表达变化的功能重要性。意义。拟议的研究将提供有关竞争性的竞争性竞争性竞争性竞争性的妇女敏感性的新型信息，以提供有关POVERNIGE的POVERNIGENT的新信息。癫痫发作围绕其每月周期聚集，但是目前尚未完全了解此疾病的病理生理学。