PROSTATE GROWTH REGULATION BY ADRENERGIC RECEPTORS

良性前列腺增生（BPH）是最常见的肿瘤 影响美国男性的疾病。 长期目标 该提案的目的是了解发展背后的机制 的BPH。 在这一背景下，本提案旨在测试 总体假设是，儿茶酚胺启动前列腺间质 增长 目前的数据表明，BPH最初是一种造口疾病， 起始事件是前列腺成纤维细胞的增殖和/或 平滑肌细胞，尽管个别因素对此负责 过程仍然未知。 最近研究表明， 在许多细胞类型（包括大鼠前列腺）中诱导有丝分裂 基质细胞），以及来自培养的血管和心脏细胞的证据 表明在肥大性和增生性 应答 此外，G-蛋白偶联受体（如 作为肾上腺素能受体）可以会聚地激活一种常见的促有丝分裂的 酪氨酸激酶受体通路;该通路涉及激活 p21ras蛋白和有丝分裂原活化蛋白（MAP）激酶， 然后引发一系列涉及细胞生长和分裂的事件。 儿茶酚胺也被证明可以调节肽生长因子 在各种细胞中生产，代表另一种方法， 儿茶酚胺可以通过一种 自分泌或旁分泌机制。 在目前的提案中，第一个 具体目的是研究去甲肾上腺素（NE）作为 一种参与启动前列腺基质增生的生长因子， 使用可生物降解的NE释放小球的啮齿动物模型。 并行 去甲肾上腺素对体外培养人前列腺细胞的促有丝分裂作用 基质细胞将在原发性和稳定的前列腺上进行 基质细胞系 第二个具体目标是检查体外效应 的NE对生长因子的生产，使用各种技术 包括RNA酶保护测定和蛋白质印迹分析。 第三 假设检查前列腺基质细胞的促有丝分裂途径， 去甲肾上腺素对ras和MAP激酶激活作用的研究 刺激培养的前列腺基质细胞;肾上腺素能受体 将使用以下方法确定参与该途径活化的 亚型选择性拮抗剂。 随后的实验将定义 细胞内途径参与有丝分裂反应， 表达编码G α和G β γ亚基的肽， 在以前的实验中已经显示出解偶联G蛋白偶联 受体促有丝分裂途径。

Benign prostatic hyperplasia (BPH) is the most common neoplastic condition affecting males in the United States. The long term objective of the proposal is to understand mechanism underlying the development of BPH. Within this context, the current proposal is designed to test the overall hypothesis that catecholamines initiate prostate stromal growth. Current data suggests BPH is initially a stomal disease with the initiating event being proliferation of prostatic fibroblasts and/or smooth muscle cells, although individual factor(s) responsible for this process remain unknown. Catecholamines have recently been shown to induce mitogenesis in a number of cell types (including rat prostate stromal cells), and evidence from cultured vascular and cardiac cells implicates catecholamines in both hypertrophic and hyperplastic responses. Furthermore, activation of G-protein coupled receptors (such as adrenergic receptors) can convergently activate a common mitogenic pathway with tyrosine kinase receptors; this pathway involves activation of p21ras proteins and mitogen activated protein (MAP) kinases which then initiate a series of events involved in cell growth and division. Catecholamines have also been shown to regulate peptide growth factor production in various cells, representing another method whereby catecholamines could indirectly modulate prostate growth through an autocrine or paracrine mechanism. In the current proposal, the first specific aim investigates the potential role of norepinephrine (NE) as a growth factor involved in initiating prostate stromal hyperplasia in a rodent model using a biodegradable NE releasing pellet. A parallel evaluation of the mitogenic effects of NE on cultured human prostate stromal cells will be performed on both primary and stable prostate stromal cell lines. The second specific aim examines in vitro effects of NE on growth factor production, using a variety of techniques including RNase protection assays and western blot analysis. The third hypothesis examines mitogenic pathways in prostate stromal cells by investigating ras and MAP kinase activation in response to NE stimulation of cultured prostate stromal cells; adrenergic receptors involved in the activation of this pathway will be determined using subtype selective antagonists. Subsequent experiments will define intracellular pathways involved in the mitogenic response by transiently expressing peptides encoding for Galpha and Gbetagamma subunits, which have been shown in previous experiments to uncouple G-protein coupled receptor mitogenic pathways.