Modulatory action of epidermal growth factor on differentiated human granulosa lutein cells: Cross-talk between ligand activated receptors for EGF and gonadotropin
Modulatory action of epidermal growth factor on differentiated human granulosa lutein cells: Cross-talk between ligand activated receptors for EGF and gonadotropin
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DOI：
10.1016/s0303-7207(96)03935-4
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发表时间：
1996-11-29
影响因子：
4.1
通讯作者：
Mukhopadhyay, AK
中科院分区：
文献类型：
--
作者：
Budnik, LT;Mukhopadhyay, AK
许多局部调节因子，包括多肽生长因子，如表皮生长因子（EGF），已被认为在人类卵巢中发挥着积极作用。为了了解 EGF 作用的生理学，有必要证明和表征卵巢细胞上这种生长因子的受体，这也是本研究的目的。我们证明使用 [I-125]EGF，该配体与 K-a 的特异性高亲和力结合位点对于人颗粒叶黄素细胞的生长培养物达到 2.2 x 10(-9) M，对于从这些细胞制备的膜部分达到 0.13 x 10(-9) M。此外，我们借助亲和交联和免疫印迹程序鉴定了 170 kD 的蛋白质作为 EGF 受体。此外，我们观察到用 EGF 短暂（0-30 分钟）预处理颗粒叶黄素细胞会导致 LH 受体偶联腺苷酸环化酶活性呈剂量和时间依赖性上调。使用 10-20 ng/ml EGF 在 10-15 分钟时达到最大效果（与未处理的细胞相比增加 159 +/- 12%，P < 0.001，n = 4）。受体酪氨酸激酶活性的特异性抑制消除了观察到的 EGF 诱导的环化酶活性敏化。体内颗粒细胞的分化是排卵和随后转化为高度分化的叶黄素细胞的先决条件，这一过程取决于提高 cAMP 产生的配体的存在。观察到的 EGF 对腺苷酸环化酶的调节可能是周期不同阶段颗粒细胞分化状态的调节成分。版权所有 (C) 1996 Elsevier Science Ireland Ltd.
A number of local regulatory factors including polypeptide growth factors like epidermal growth factor (EGF) have been suggested to play an active role within the human ovary. In order to understand the physiology of EGFs action, it is essential to demonstrate and characterize the receptors for this growth factor on ovarian cells which was the aim of this study. We demonstrate using [I-125]EGF that specific high affinity binding sites with K-a for this ligand reaching 2.2 x 10(-9) M for growing cultures of human granulosa-lutein cells and 0.13 x 10(-9) M for the membrane fraction prepared from these cells. Additionally we have identified a 170 kD protein as the EGF receptor with the help of affinity cross linking and immunoblotting procedures. Furthermore, we observed that a pretreatment of granulosa lutein cells with EGF for a short duration (0-30 min) leads to a dose- and time dependent upregulation of the LH-receptor-coupled adenylate cyclase activity. A maximal effect (159 +/- 12% increase compared with untreated cells, P < 0.001, n = 4) was reached at 10-15 min with 10-20 ng/ml EGF. Specific inhibition of the receptor tyrosine kinase activity abolished the observed EGF-induced sensitization of the cyclase activity. Differentiation of granulosa cells in vivo is a prerequisite for ovulation and later transformation into highly differentiated lutein cells, a process depending on the presence of ligands that elevate cAMP production. The observed modulating of the adenylate cyclase by EGF could be a regulatory component for the differentiated status of the granulosa cells during different phases of the cycle. Copyright (C) 1996 Elsevier Science Ireland Ltd.