Testis

Follicle Stimulating Hormone Regulates Both Sertoli Cell and Spermatogonial Populations In the Adult Photoinhibited Djungarian Hamster Testis

Abstract
The hormones that regulate spermatogonial development are ill defined, in part due to lack of appropriate experimental models. The photoinhibited hamster model provides a rich source of spermatogonia, thus making it an ideal model to study their control. This study aimed to assess the effects of FSH, in the absence of testosterone, on the re-initiation of Sertoli cell and spermatogonial development in the photosensitive adult Djungarian hamster. Hamsters raised under long photoperiods (LD, 16L:8D) were exposed to short photoperiods (SD, 8L:16D) for 11 weeks leading to suppression of gonadotropins and regression of testicular function. Groups of 10 animals then received FSH alone or in combination with the anti-androgen, flutamide for 7 days. Two control groups maintained either under long or short photoperiods were treated with vehicle. Sertoli and germ cell number were then determined using the optical dissector (sic) stereological technique. The number of Sertoli cells, type A spermatogonia, type B spermatogonia/preleptotene spermatocytes and leptotene/zygotene spermatocytes were suppressed in short day controls, to 66%, 34%, 19% and 10% (all P<0.01) of long day control values, respectively. Later germ cell types were not detected. FSH treatment, with or without flutamide, increased Sertoli cell number (P<0.01) to normal long day values. Similarly, FSH treatment in the absence/presence of flutamide increased type A spermatogonia, type B spermatogonia/preleptotene spermatocytes and leptotene/zygotene spermatocytes to ~85%, 69% and 80% (all P<0.01) of long day controls, respectively. Our data demonstrate that the re-initiation of spermatogonial maturation in this model is dependent on FSH, in the absence of androgens. Surprisingly the adult Sertoli cell population in this model is also hormone-dependent. This naturally occurring model provides a unique opportunity to understand the mechanisms (apoptotic and/or proliferative) by which FSH regulates Sertoli and germ cell development in the adult animal.

Key words: Testis • Follicle-stimulating hormone • Sertoli cells • Spermatogenesis

This article has been cited by other articles:

				G. A Tarulli, S. J Meachem, S. Schlatt, and P. G Stanton Regulation of testicular tight junctions by gonadotrophins in the adult Djungarian hamster in vivo Reproduction, June 1, 2008; 135(6): 867 - 877. [Abstract] [Full Text] [PDF]

				S. J Meachem, S. Schlatt, S. M Ruwanpura, and P. G Stanton The effect of testosterone, dihydrotestosterone and oestradiol on the re-initiation of spermatogenesis in the adult photoinhibited Djungarian hamster J. Endocrinol., March 1, 2007; 192(3): 553 - 561. [Abstract] [Full Text] [PDF]

				S. H. Liew, S. J. Meachem, and M. P. Hedger A Stereological Analysis of the Response of Spermatogenesis to an Acute Inflammatory Episode in Adult Rats J Androl, January 1, 2007; 28(1): 176 - 185. [Abstract] [Full Text] [PDF]

				B. Furnes and J. Schimenti Fast forward to new genes in mammalian reproduction J. Physiol., January 1, 2007; 578(1): 25 - 32. [Abstract] [Full Text] [PDF]

				K. L. Matthiesson, R. I. McLachlan, L. O'Donnell, M. Frydenberg, D. M. Robertson, P. G. Stanton, and S. J. Meachem The Relative Roles of Follicle-Stimulating Hormone and Luteinizing Hormone in Maintaining Spermatogonial Maturation and Spermiation in Normal Men J. Clin. Endocrinol. Metab., October 1, 2006; 91(10): 3962 - 3969. [Abstract] [Full Text] [PDF]

				K. L. Matthiesson and R. I. McLachlan Male hormonal contraception: concept proven, product in sight? Hum. Reprod. Update, July 1, 2006; 12(4): 463 - 482. [Abstract] [Full Text] [PDF]

				G. A. Tarulli, P. G. Stanton, A. Lerchl, and S. J. Meachem Adult Sertoli Cells Are Not Terminally Differentiated in the Djungarian Hamster: Effect of FSH on Proliferation and Junction Protein Organization Biol Reprod, May 1, 2006; 74(5): 798 - 806. [Abstract] [Full Text] [PDF]

				R. W. Schulz, S. Menting, J. Bogerd, L. R. Franca, D. A.R. Vilela, and H. P. Godinho Sertoli Cell Proliferation in the Adult Testis--Evidence from Two Fish Species Belonging to Different Orders Biol Reprod, November 1, 2005; 73(5): 891 - 898. [Abstract] [Full Text] [PDF]