골든 햄스터의 고환 조직의 조직학적 변화에 미치는 광주기 처리의 효과
Effects of Photoperiod Treatment on Histological Changes in Testis Tissues of the Golden Hamster
1
조회
0
다운로드
0
인용
0
참고문헌
키워드
초록
.
Abstract
Many mammals in temperate zones are affected by the distinctive changes of the four seasons in these zones. Their reproductive status is active in the summer climate and inactive during severe winter weather. The golden hamster (Mesocricetus auratus) is seasonal breeding animal whose sexual activities are regulated by photoperoidism. The reproduction and metabolism are activated by long summer days (LD) and inhibited by short winter days (SD). After several months of SD, animals become refractory to this inhibitory photoperiod and spontaneously revert to LD-like physiology. The suprachiasmatic nuclei (SCN) house the primary circadian oscillator in mammals. Seasonal changes in the photic input to this structure control many annual physiological rhythms via SCN-regulated pineal melatonin secretion, which provides an internal endocrine signal representing photoperiod. The aim of this study was to assess the variation in the morphology of the testis in relation to the natural photoperiod in male golden hamsters. The hamsters were castrated at different weeks (2, 5, 8, and 15). The cell numbers of tubules with spermatogonia (SG), spermatocyte (SC), spermatids (ST), and spermatozoa (SZ) were recorded in each sample. The results showed that testicular regression of golden hamsters occurred in the SD-treated animals. The present investigation determines that the effects of the photoperiod on the reproduction of male golden hamsters. It was also found that the circadian period increases the rate of reproductive inhibition in animals exposed to inhibitory photoperiods.
참고문헌 (12)
- Anderson KD, "Photoperiodic control of testicular size in the golden hamster: lack of a role for the deep pineal gland", J Pineal Res, 2, pp.99~107 (1985)
- Berndtson WE, "Circulating LH and FSH levels and teticular funtion in hamsters during light deprivation and subsequent photoperiodic stimulation", Endocrinology, 95, pp.195~205 (1974)
- Elliott JA, "Circadian rhythm and photoperiodic time measurement in mammals", Fed Proc, 35, pp.2339~2346 (1976)
- Golman BD, "Prolactin release in golden hamsters: photoperiod and gonadal influences", Biol Reprod, 24, pp.287~292 (1981)
- Hastings MH, "Differential effects of photoperoidic history on the responeses of gonadotrophins and prolactin to intermediate daylengths in the male Syrian hamster", J Biol Rhythms, 3, pp.335~350 (1989)
- Leslie PG, "Male reproductive system", pp.379~ (2007), Lippincott Williams & Wikins Inc publishing
- McLachlan RI, "Testosterone promotes the conversion of round spermatids between stages VII and VIII of the rat spermatogenic cycle", Endocrinology, 135, pp.2608~2614 (1994)
- Rudeen PK, "Influence of a skeleton photoperiod on reproductive organ atrophy in the male golden hamster", J Reprod Fertil, 60, pp.279~283 (1980)
- Stetson MH, "Tate-Ostroff. Hormonal regulation of the annual reproductive cycle of golden hamsters", Gen Comp Endocr, 45, pp.329~344 (1981)
- Stetson MH, "The pineal Gland", pp.109~153 (1984), Raven Press publishing
- Tamarkin L, "Regulation of serum gonadotropins by photoperiod and testicular hormone in the Syrian hamster", Endocrinology, 99, pp.1528~1533 (1976)
- van Haaster LH, "Effect of prenatal and postnatal photoperiod on spermatogenic development in the Djungarian hamster (Phodopus sungorus sungorus)", J Reprod Fertil, 97, pp.223~232 (1993)