Hormonal control of spermatogenesis: expression of FSJH receptor and androgen receptor genes

FSH and testosterone are the main hormonal regulators of spermatogenesis. The actions of androgens and FSH are mediated by their respective receptors. Receptor gene expression (mRNA and protein). is an important determinant of hormone action. Biochemical aspects of the regulation of androgen and FSH receptor gene expression in the testis were chosen as the subject of the studies described in this thesis. Regulation of the expression of the receptor genes was studied at the level of gene transcription, and at the level of mRNA and protein expression. In Chapters 2-4, a detailed characterization is given of the effects of FSH on androgen and FSH receptor mRNA and protein expression in cultured immature Sertoli cells. For the androgen receptor, these findings were extended by measurements of androgen receptor gene transcription initiation rate in cultured immature Sertoli cells and LNCaP Oymph node carcinoma of the prostate) cells (Chapter 5). Preliminary results concerning a putative paracrine factor, produced by Sertoli cells and affecting androgen receptor mRNA expression in peritubular myoid cells, are presented in Chapter 6. The effects of testosterone deprivation iD. vivo on androgen receptor mRNA and protein expression in the adult rat testis were examined as described in Chapter 7.ffi vitro effects of testosterone on androgen receptor gene expression in cultured testicular cells and LNCaP cells are described in the Chapters 2, 3 and 5. In the General Discussion (Chapter 8) we have considered some aspects of regulation of spermatogenesis by FSH and testosterone and have discussed them in relation to our experimental data as well as in a broader perspective. This way, we hope that the results which we have presented, and discussions which we have tried to initiate, may contribute to research concerning hormonal control of spermatogenesis, now and in the future