CONSEQUENCES OF MALE LH RECEPTOR GENE KNOCKOUT

描述：（由申请人提供）我们最近成功地创建了 促黄体生成素受体基因敲除（LHRKO）小鼠， 同源DNA重组技术。靶向缺失LHR基因， 外显子1区域的启动子完全失活了该基因， 导致在纯合子动物的性腺中检测不到LHR。在LHR 无效雄性不致死，但不育，而它们的杂合子同窝出生的 看起来很正常纯合子男性的外生殖器和内生殖器 严重发育不全，精子发生在 精母细胞该表型被认为是由雄激素减少引起的 睾丸间质细胞的LH刺激的情况下的影响。 睾丸替代治疗，尽管睾丸功能改善 形态学和精子发生，没有恢复男性生育能力，作为纯合子 男性的精子数量和活力都很低。鉴于LH 具有广泛的作用，通过其在性腺和非性腺中的受体介导 组织，如精子和附睾中的功能性LHR， 从LHRKO男性获得的结果，我们假设LH的贡献 雄激素对精子发生的作用可能不仅仅是作用于睾丸间质细胞 生产拥有这种独特的LHRKO小鼠模型使我们能够选择性地 研究LH在生殖生物学中的重要作用。这一拟议 研究的目的是寻找LHRKO不孕症的潜在原因 即使在雄激素替代治疗后。因此，这笔小额赠款 应用程序将只集中在两个方面，这是已知的关键， 精子发生和精子成熟，列为两个具体目标：1） 研究LHRKO对生精细胞的影响。2)确定 LHRKO对精子成熟的影响。这些功能数据对于 我们进一步研究LH在男性生殖中的重要作用， 生物化学和分子水平。遗传缺陷导致的人类不育 在LHR或LH-p亚基中越来越多地被认识到，但没有天然存在 具有相应突变的动物模型可用于研究。 因此，从这些LHRKO小鼠获得的数据不仅将推进我们的研究， 了解LH的作用对正常男性的重要性 生殖生理学，但也将有助于开发更好的诊断 男性不育症的治疗选择，相反， 有效和安全的男性避孕试剂。

DESCRIPTION: (Provided by the Applicant) We recently succeeded in creating mice with the luteinizing hormone receptor gene knockout (LHRKO) by a homologous DNA recombination technology. Targeting deletion of the LHR gene at the promoter to exon one region completely inactivated the gene, which resulted in no detectable LHR in the gonads of homozygous animals. The LHR null males are not lethal but sterile, while their heterozygous littermates appear to be normal. The external and internal genitalia of homozygous males were grossly underdeveloped and spermatogenesis was arrested at the spermatocytes. The phenotype is believed to be caused by decreased androgen influence in the absence of LH stimulation of testicular Leydig cells. Testosterone replacement therapy, in spite of improvement in testicular morphology and spermatogenesis, did not restore male fertility, as homozygous males have very low sperm numbers and motility. In view of the fact that LH has pervasive actions, mediated by its receptors in gonadal and nongonadal tissues such as functional LHR in sperm and epididymis and with preliminary results obtained from LHRKO males, we hypothesize that the contribution of LH to spermatogenesis may be more than just acts on Leydig cells for androgen production. Having this unique LHRKO mouse model enables us to selectively investigate the crucial roles of LH in reproductive biology. This proposed research is aimed at searching for potential causes of infertility in LHRKO males even after androgen replacement therapy. Therefore, this small grant application will only focus on two aspects that are known to be critical in spermatogenesis and sperm maturation, listed as two specific aims: 1) investigating the effect of LHRKO on spermatogenic cells. 2) determining the effect of LHRKO on sperm maturation. These functional data are essential for us to further investigate the vital role of LH in male reproduction at biochemical and molecular levels. Infertility in human due to genetic defects in LHR or LH-p subunit are increasingly recognized, but there are no naturally occurring animal models with the corresponding mutations available for study. Thus, the data obtained from these LHRKO mice will not only advance our understanding on how important the actions of LH are for normal male reproductive physiology but will also facilitate developing better diagnostic and therapeutic options for male infertility and, conversely, developing more effective and safer male contraceptive reagents.