Spermiogenesis in hibernating golden hamsters

Smit-Vis, J.H.; Akkerman-Bellaart, M. A.

doi:10.1007/bf02146881

Cited by 16 publications

(2 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It has been established that the onset of spermatogenic activity occurs during the denning period in black bears [5,24] and brown bears [25] as well as in other deep hibernating mammals such as ground squirrels [10,12], European hedgehogs [4,21], and golden hamsters [22]. Serum testosterone profiles of black bears indicated that the activity of the reproductive endocrine system begins to increase during denning [11,17,24].…”

mentioning

confidence: 99%

Sex Steroid and Prolactin Profiles in Male American Black Bears (Ursus americanus) during Denning.

Tsubota

Garshelis

Nelson

et al. 1999

The Journal of Veterinary Medical Science

View full text Add to dashboard Cite

ABSTRACT. Serum sex steroid and prolactin profiles were examined in the male American black bear, Ursus americanus during denning. Sera collected in December and the following March from 8 denning male black bears in Minnesota, U.S.A. were assayed for testosterone, estradiol-17β and prolactin. Eight bears were confirmed to be the denning mode based on a serum urea to creatinine ratio less than 10. Serum testosterone concentrations tended to increase from December to the subsequent March whereas serum estradiol-17β concentrations tended to decrease during this period. There were few changes in serum prolactin concentrations between December and March. These findings suggest that spermatogenesis and testicular steroidogenesis initiated during denning may be influenced by changes in serum sex steroid concentrations in the American black bear.-KEY WORDS: bear, denning, sex steroid.

show abstract

mentioning

confidence: 99%

Sex Steroid and Prolactin Profiles in Male American Black Bears (Ursus americanus) during Denning.

Tsubota

Garshelis

Nelson

et al. 1999

The Journal of Veterinary Medical Science

View full text Add to dashboard Cite

show abstract

“…Secretion pulses seem to occur during spontaneous arousal (Dussart and Richoux, 1973), and consequently the increased activity may be either facilitated by or dependent on increased spontaneous arousals occurring atthattime (Racey, 1974). Popovic (1960) (Smit-Vis and Akkerman-Bellaart, 1967 ;Reiter, 1968Reiter, , 1972Hoffmann, 1973Hoffmann, , 1978 …”

mentioning

confidence: 99%

The reproductive cycle in the male hedgehog (Erinaceus europaeus L.) : a study of endocrine and exocrine testicular functions

Saboureau¹,

Dutourné²

1981

Reprod. Nutr. Dévelop.

View full text Add to dashboard Cite

show abstract

Evidence for refractoriness of the pituitary‐gonadal axis to the pineal gland in golden hamsters and its possible implications in annual reproductive rhythms

Reíter

1972

Anat. Rec.

157

View full text Add to dashboard Cite

The testes of adult hamsters maintained in short daily photoperiods (1ight:dark [LD] cycles of 1:23, in hours) undergo regression within ten weeks and spontaneous regeneration within about 30 weeks. Thereafter (at least up to 80 weeks), as long as these animals are kept in short photoperiods the gonads do not experience a second atrophic response. After the 30 week period of dark exposure, if the hamsters are moved into a long photoperiodic environment (LD 14:lO) for either one or ten weeks and are then returned to short photoperiods, the gonads do not involute a second time. However, if the duration of exposure to LD 14: 10 is increased to 22 weeks, the return to LD 1 :23 causes the gonads to degenerate. The regressive responses of the testes never occur in hamsters that have been pinealectomized indicating that the observed changes are mediated by this gland. The inability of darkness and, thus the pineal gland, to induce a second gonadal involution unless the hamsters are maintained in LD cycles of 14:lO for 22 weeks (after a 30 week period of dark exposure) may be explicable in terms of ( l ) , a transient refractoriness of the brain to the pineal antigonadotropic principle or (2), the temporary failure of the pineal to be activated by short daily photoperiods.

show abstract

Spermiogenesis in hibernating golden hamsters

Cited by 16 publications

References 3 publications

Sex Steroid and Prolactin Profiles in Male American Black Bears (Ursus americanus) during Denning.

Sex Steroid and Prolactin Profiles in Male American Black Bears (Ursus americanus) during Denning.

The reproductive cycle in the male hedgehog (Erinaceus europaeus L.) : a study of endocrine and exocrine testicular functions

Evidence for refractoriness of the pituitary‐gonadal axis to the pineal gland in golden hamsters and its possible implications in annual reproductive rhythms

Contact Info

Product

Resources

About