Lutropin/choriogonadotropin stimulate the proliferation of primary cultures of rat leydig cells through a pathway that involves activation of the extracellularly regulated kinase 1/2 cascade
Lutropin/choriogonadotropin stimulate the proliferation of primary cultures of rat leydig cells through a pathway that involves activation of the extracellularly regulated kinase 1/2 cascade
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DOI：
10.1210/en.2007-0160
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发表时间：
2007-07-01
期刊：
影响因子：
4.8
通讯作者：
Ascoli, Mario
中科院分区：
文献类型：
--
作者：
Shiraishi, Koji;Ascoli, Mario
分别从21日龄和35d龄大鼠的睾丸组织中分离培养出祖细胞和幼鼠睾丸间质细胞。3β-羟基类固醇脱氢酶染色显示，培养4-6d后细胞数量保持均匀，但不能结合I-125-人绒毛膜促性腺激素(HCG)，也不能对hCG产生经典的促黄体生成素受体(LHR)介导的反应，包括cAMP和肌醇磷酸蓄积、类固醇生物合成或ERK1/2的磷酸化。人LHR(HLHR)的腺病毒感染使hLHR以每细胞约25000个受体的密度表达，并使细胞对hCG的反应增加，cAMP和肌醇磷酸积累增加，类固醇生物合成和ERK1/2的磷酸化。尽管祖细胞和未成熟细胞能够通过增加孕酮来响应hCG，但只有未成熟细胞以增加睾酮的方式反应。除了这些经典的LHR介导的反应外，表达重组hLHR的祖细胞或未成熟大鼠间质细胞的原代培养在hCG孵育时增殖旺盛，这种增殖反应对ERK1/2磷酸化抑制剂敏感。这些研究建立了一种新的实验范式，可用于研究间质细胞对黄体生成素/卵泡刺激素的增殖反应。我们的结论是，激活LHR刺激的间质细胞增殖需要激活ERK1/2级联反应。
Primary cultures of progenitor and immature rat Leydig cells were established from the testes of 21- and 35-d-old rats, respectively. The cell population remained homogeneous after 4-6 d in culture as judged by staining for 3 beta-hydroxysteroid dehydrogenase, but the cells were unable to bind I-125-human chorionic gonadotropin (hCG) or to respond to hCG with classical LH receptor (LHR)-mediated responses, including cAMP and inositol phosphate accumulation, steroid biosynthesis, or the phosphorylation of ERK1/2. Infection of primary cultures with recombinant adenovirus coding for beta-galactosidase showed that approximately 65% of the cells are infected. Infection with adenovirus coding for the human LHR (hLHR) allowed for expression of the hLHR at a density of approximately 25,000 receptors per cell and allowed the cells to respond to hCG with increases in cAMP and inositol phosphate accumulation, steroid biosynthesis, and the phosphorylation of ERK1/2. Although progenitor and immature cells were able to respond to hCG with an increase in progesterone, only the immature cells responded with an increase in testosterone. In addition to these classical LHR-mediated responses, the primary cultures of progenitor or immature rat Leydig cells expressing the recombinant hLHR proliferated robustly when incubated with hCG, and this proliferative response was sensitive to an inhibitor of ERK1/2 phosphorylation. These studies establish a novel experimental paradigm that can be used to study the proliferative response of Leydig cells to LH/CG. We conclude that activation of the LHR-provoked Leydig cell proliferation requires activation of the ERK1/2 cascade.