LKS AND LKUR IN GRANULOSA CELLS

这项研究的长期目标是增加对离子的了解 卵巢颗粒细胞(GC)中存在通道，提示可能 离子通道在GC功能中的作用。拟议的项目将专注于 具体地说，就其监管属性和功能意义而言 OF：缓慢激活、非失活延迟整流K电流 (IKS)和超快激式延迟整流器K电流 (IKUR)。要检验的主要假设是1)Iks和Ikur是 颗粒细胞所涉及的信号转导系统的调控 生长和分化；2)Iks、Ikur或两者都有 是正常颗粒细胞成熟所必需的。电生理学 细胞培养技术将被用来解决这些假设 试验性的。生化技术将被用来定义 对IKUR有贡献的通道蛋白。具体地说，实验 目的是：1)比较颗粒细胞iK的特性 心脏慢延迟整流钾电流和心电活动。 与Min-K和KvLQT1共表达相关的慢K电流 结合形成功能性Ks通道的通道蛋白；2) 颗粒细胞IKur与延迟性颗粒细胞特性的比较 其他电池类型中的整流K电流，以及延迟整流K 与Kv(Shaker亚家族)通道表达相关的电流 对IKUR有贡献的蛋白质；3)决定 不同钾通道拮抗剂对颗粒细胞的抑制作用 成熟与IKs或IKUR的阻断有关。 不仅要确定IKS的生理作用(S)，这将是至关重要的 与IKUR在GC成熟的同时，也要比较其药理作用 延时整流电流与GC电流的关系 其他细胞。K通道已被确定为治疗靶点 在心脏、平滑肌、淋巴细胞和脑中(Carmeleit，1991)。气相色谱 IKS和IKUR可能代表两个新的辅助目标 生殖，或用于治疗的药物的潜在毒性部位 心律失常、哮喘、大小便失禁、免疫抑制或癫痫。

The long-term goals of the research are to increase knowledge about ion channels present in ovarian granulosa cells (GC), and suggest potential roles for ion channels in GC function. The proposed project will focus specifically on the regulatory properties and functional significance of: a slowly activating, non-inactivating delayed rectifier K+ current (IKs), and an utra-rapidly activating delayed rectifier K+ curren (IKur). The major hypotheses to be tested are 1) IKs and IKur are modulated by signal transduction systems implicated in granulosa cell growth and differentiation; 2) IKs, IKur, or both potassium conductances are required for normal granulosa cell maturation. Electrophysiological and cell culture techniques will be used to address these hypotheses experimentally. Biochemical techniques will be used to define the channel proteins that contribute to IKur. Specifically, experiments were designed to: 1) Compare the properties of granulosa cell IKs to those of the cardiac slow delayed rectifier K+ current, and those of the slow K+ currents associated with co-expression of min-K and KvLQT1, the channel proteins that associate to form functional Ks channels; 2) Compare the properties of granulosa cell IKur to those of delayed rectifier K+ currents in other cell types, and delayed rectifier K+ currents associated with expression of the Kv (Shaker subfamily) channel proteins that contribute to IKur; 3) Determine whether or not the inhibitory effects of various K+ channel antagonists on granulosa cell maturation are related to blockade of IKs or IKur. It will be critical not only to define the physiological role(s) of IKs and IKur in GC maturation, but also to compare the pharmacological profiles of the GC currents to those of delayed rectifier currents in other cells. K+ channels have been identified as therapeutic targets in heart, smooth muscle, lymphocytes, and brain (Carmeleit, 1991). GC IKs and IKur may represent either novel targets for assisted reproduction, or potential sites of toxicity for drugs designed to treat arrhythmias, asthma, incontinence, immunosuppression or epilepsy.