The relative roles of follicle-stimulating hormone and luteinizing hormone in maintaining spermatogonial maturation and spermiation in normal men.
BACKGROUND
Male hormonal contraception via gonadotropin and intratesticular androgen withdrawal disrupts spermatogenesis at two principal sites: 1) spermatogonial maturation, and 2) spermiation.


OBJECTIVE
The objective of this study was to explore the relative dependence of each stage of germ cell development on FSH and LH/intratesticular androgen action.


METHODS
Eighteen men enrolled in this prospective, randomized 14-wk study at Prince Henry's Institute.


METHODS
Subjects (n = 6/group) were assigned to 6 wk of 1) testosterone (T) implant (4 x 200 mg sc once)+depot medroxy progesterone acetate (DMPA; 150 mg im once); 2) T implant+DMPA+FSH (300 IU sc twice weekly); and 3) T implant+DMPA+human chorionic gonadotropin (hCG; 1000 IU sc twice weekly as an LH substitute). Men then underwent a vasectomy and testicular biopsy with previously reported control data used for comparison.


METHODS
Germ cell number (assessed by the optical disector stereological approach) and intratesticular androgen levels were determined.


RESULTS
T+DMPA alone significantly suppressed type B spermatogonia, preleptotene through to pachytene spermatocytes, and round spermatids from control (P < 0.05). All germ cell subtypes were maintained at control levels by either FSH or LH activity, except pachytene spermatocytes, which were found to be lower in the hCG vs. FSH (P < 0.01) and control groups (P < 0.05).


CONCLUSIONS
FSH and LH maintained spermatogenesis independently in this gonadotropin-suppressed model. Compared with LH, FSH showed better maintenance of pachytene spermatocyte number, whereas improved conversion to round spermatids was suggested with hCG treatment. Future contraceptive treatment strategies must consider independent regulation of spermatogenesis by both FSH and LH/intratesticular androgens for maximum efficacy.
Matthiesson
Kati L
KL
Prince Henry's Institute, and Departments of Obstetrics and Gynaecology, Monash University, P.O. Box 5152, Monash Medical Center, Clayton, Victoria 3168, Australia. kati.matthiesson@princehenrys.org
McLachlan
Robert I
RI
O'Donnell
Liza
L
Frydenberg
Mark
M
Robertson
David M
DM
Stanton
Peter G
PG
Meachem
Sarah J
SJ
D000328:Adult; D006063:Chorionic Gonadotropin / Q000494:pharmacology; D004958:Estradiol / Q000097:blood; D005640:Follicle Stimulating Hormone / Q000097:blood / Q000502:physiology*; D006801:Humans; D007986:Luteinizing Hormone / Q000097:blood / Q000502:physiology*; D008297:Male; D017258:Medroxyprogesterone Acetate / Q000008:administration & dosage; D008875:Middle Aged; D011446:Prospective Studies; D013076:Sperm Count; D013091:Spermatogenesis; D013093:Spermatogonia / Q000502:physiology*; D013737:Testis / Q000737:chemistry; D013739:Testosterone / Q000008:administration & dosage / Q000097:blood
D006063:Chorionic Gonadotropin; D013739:Testosterone; D004958:Estradiol; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D017258:Medroxyprogesterone Acetate