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The effect of testosterone, dihydrotestosterone and oestradiol on the re-initiation of spermatogenesis in the adult photoinhibited Djungarian hamster.

Meachem SJ, Schlatt S, Ruwanpura SM, Stanton PG - J. Endocrinol. (2007)

Bottom Line: The number of germ cells in SD animals was reduced (all P < 0.001) to levels reported.DHT increased the number of type B spermatogonia/preleptotene spermatocytes, leptotene/zygotene and pachytene spermatocytes by 3.5-, 5.7- and 21-fold above SD (all P < 0.01) respectively, compared with a 2.2-fold (P < 0.01), 2.4-fold (not significant, NS) and 6-fold (NS) in E-treated animals respectively.Exogenous T had little effect on cell numbers or serum FSH compared with SD controls.

View Article: PubMed Central - PubMed

Affiliation: Prince Henry's Institute of Medical Research, Level 4, 43-51 Kanooka Grove, Clayton, Victoria, 3168 Australia.

ABSTRACT
The roles of testosterone (T) and its metabolites on hamster spermatogenesis are poorly defined. This study assessed the effects of T, dihydrotestosterone (DHT) and oestradiol (E) on the re-initiation of spermatogenesis in the adult Djungarian hamster. Hamsters raised under long photoperiods (LD, 16 h light:8 h darkness) were exposed to short photoperiods (SD, 8 h light:16 h darkness) for 11 weeks to suppress gonadotrophins. Groups of eight animals then received T, DHT and E for 5 weeks. Cell numbers were determined using the optical disector (sic). The number of Sertoli cells was suppressed in SD controls to 48% (P < 0.001) of LD control and restored either fully or partially by exogenous DHTand E (2.6- and 1.8-fold above SD levels) respectively, corresponding with a twofold elevation of serum FSH. The number of germ cells in SD animals was reduced (all P < 0.001) to levels reported. The number of type A spermatogonia increased in line with the rise in Sertoli cell number, by 2.6-fold (P < 0.01) and 1.8-fold (NS) above SD controls after DHT and E treatments respectively. DHT increased the number of type B spermatogonia/preleptotene spermatocytes, leptotene/zygotene and pachytene spermatocytes by 3.5-, 5.7- and 21-fold above SD (all P < 0.01) respectively, compared with a 2.2-fold (P < 0.01), 2.4-fold (not significant, NS) and 6-fold (NS) in E-treated animals respectively. Exogenous T had little effect on cell numbers or serum FSH compared with SD controls. Spermatids were rarely observed after steroid treatment. We believe this study suggests that steroids can regulate the re-initiation of early spermatogenic cells via a mechanism which includes FSH.

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Related in: MedlinePlus

Body and organ weights in photo-stimulated (long day, LD) adult Djungarian hamsters that were exposed to short photoperiods (short day, SD) for 11 weeks. Hamsters were then given 3 cm Silastic implants filled with testosterone (T), oestradiol (E, 10% in cholesterol) or dihydrotestosterone (DHT) for 33 days. LD and SD controls received 3 cm cholesterol-filled Silastic implants. Data are means±s.e.m., n=8 hamsters/group. Letters denote significant differences between the treatment groups at P<0·05 or less (see text for specifics).
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fig1: Body and organ weights in photo-stimulated (long day, LD) adult Djungarian hamsters that were exposed to short photoperiods (short day, SD) for 11 weeks. Hamsters were then given 3 cm Silastic implants filled with testosterone (T), oestradiol (E, 10% in cholesterol) or dihydrotestosterone (DHT) for 33 days. LD and SD controls received 3 cm cholesterol-filled Silastic implants. Data are means±s.e.m., n=8 hamsters/group. Letters denote significant differences between the treatment groups at P<0·05 or less (see text for specifics).

Mentions: Body weights were reduced (P<0·001) in SD control compared with LD controls (Fig. 1). Steroid administration did not affect body weight compared with their corresponding SD controls (Fig. 1).


The effect of testosterone, dihydrotestosterone and oestradiol on the re-initiation of spermatogenesis in the adult photoinhibited Djungarian hamster.

Meachem SJ, Schlatt S, Ruwanpura SM, Stanton PG - J. Endocrinol. (2007)

Body and organ weights in photo-stimulated (long day, LD) adult Djungarian hamsters that were exposed to short photoperiods (short day, SD) for 11 weeks. Hamsters were then given 3 cm Silastic implants filled with testosterone (T), oestradiol (E, 10% in cholesterol) or dihydrotestosterone (DHT) for 33 days. LD and SD controls received 3 cm cholesterol-filled Silastic implants. Data are means±s.e.m., n=8 hamsters/group. Letters denote significant differences between the treatment groups at P<0·05 or less (see text for specifics).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC1994566&req=5

fig1: Body and organ weights in photo-stimulated (long day, LD) adult Djungarian hamsters that were exposed to short photoperiods (short day, SD) for 11 weeks. Hamsters were then given 3 cm Silastic implants filled with testosterone (T), oestradiol (E, 10% in cholesterol) or dihydrotestosterone (DHT) for 33 days. LD and SD controls received 3 cm cholesterol-filled Silastic implants. Data are means±s.e.m., n=8 hamsters/group. Letters denote significant differences between the treatment groups at P<0·05 or less (see text for specifics).
Mentions: Body weights were reduced (P<0·001) in SD control compared with LD controls (Fig. 1). Steroid administration did not affect body weight compared with their corresponding SD controls (Fig. 1).

Bottom Line: The number of germ cells in SD animals was reduced (all P < 0.001) to levels reported.DHT increased the number of type B spermatogonia/preleptotene spermatocytes, leptotene/zygotene and pachytene spermatocytes by 3.5-, 5.7- and 21-fold above SD (all P < 0.01) respectively, compared with a 2.2-fold (P < 0.01), 2.4-fold (not significant, NS) and 6-fold (NS) in E-treated animals respectively.Exogenous T had little effect on cell numbers or serum FSH compared with SD controls.

View Article: PubMed Central - PubMed

Affiliation: Prince Henry's Institute of Medical Research, Level 4, 43-51 Kanooka Grove, Clayton, Victoria, 3168 Australia.

ABSTRACT
The roles of testosterone (T) and its metabolites on hamster spermatogenesis are poorly defined. This study assessed the effects of T, dihydrotestosterone (DHT) and oestradiol (E) on the re-initiation of spermatogenesis in the adult Djungarian hamster. Hamsters raised under long photoperiods (LD, 16 h light:8 h darkness) were exposed to short photoperiods (SD, 8 h light:16 h darkness) for 11 weeks to suppress gonadotrophins. Groups of eight animals then received T, DHT and E for 5 weeks. Cell numbers were determined using the optical disector (sic). The number of Sertoli cells was suppressed in SD controls to 48% (P < 0.001) of LD control and restored either fully or partially by exogenous DHTand E (2.6- and 1.8-fold above SD levels) respectively, corresponding with a twofold elevation of serum FSH. The number of germ cells in SD animals was reduced (all P < 0.001) to levels reported. The number of type A spermatogonia increased in line with the rise in Sertoli cell number, by 2.6-fold (P < 0.01) and 1.8-fold (NS) above SD controls after DHT and E treatments respectively. DHT increased the number of type B spermatogonia/preleptotene spermatocytes, leptotene/zygotene and pachytene spermatocytes by 3.5-, 5.7- and 21-fold above SD (all P < 0.01) respectively, compared with a 2.2-fold (P < 0.01), 2.4-fold (not significant, NS) and 6-fold (NS) in E-treated animals respectively. Exogenous T had little effect on cell numbers or serum FSH compared with SD controls. Spermatids were rarely observed after steroid treatment. We believe this study suggests that steroids can regulate the re-initiation of early spermatogenic cells via a mechanism which includes FSH.

Show MeSH
Related in: MedlinePlus