Extragonadal LH/hCG action—Not yet time to rewrite textbooks
- 作者：Tomi Pakarainen ; Petteri Ahtiainen ; Fu-Ping Zhang ; Susana Rulli ; Matti Poutanen ; Ilpo Huhtaniemi
- 关键词：Luteinizing hormone (LH) ; Human chorionic gonadotropin (hCG) ; LH/hCG receptor (R) ; Testis ; Ovary ; Transgenic mouse ; Knockout mouse ; Gonadal function ; Extragonadal LH/hCG action
- 刊名：Molecular and Cellular Endocrinology
- 出版年：2007
- 期刊代码：109_03037207
- 类别：bio
- 出版时间：15 April 2007
- 卷：269
- 期：1-2
- 页码：9-16
- 文件大小：1178 K
摘要
Gonadotropins are indispensable in both sexes in the regulation of gonadal sex steroid production and gametogenesis. In addition to their well-established classical actions, numerous recent publications have indicated the presence and function of luteinizing hormone/chorionic gonadotropin receptors (LH/hCG-R) in a variety of extragonadal tissues. However, the physiological significance of such effects has remained unclear. We have generated two genetically modified mouse models, one with excessive production of hCG and the other with targeted disruption of LH/hCG-R gene, and used them to address the functions of LH and hCG. Numerous gonadal and extragonadal phenotypes were found in the models with the two extremes of LH/hCG action. However, when the extragonadal effects were scrutinized in greater detail, they all appeared to arise through modification of gonadal function, either through enhanced or inhibited response to LH/hCG stimulation. Hence, further evidence is needed before the extragonadal LH/hCG-R expression can be considered functionally significant.