Photoperiod control of the melatonin rhythm and reproductive maturation in the juvenile Djungarian hamster: 60-Hz magnetic field exposure effects.
Photoperiod control of the melatonin rhythm and reproductive maturation in the juvenile Djungarian hamster: 60-Hz magnetic field exposure effects.
复制标题
幼年 Djungarian 仓鼠褪黑激素节律和生殖成熟的光周期控制：60 Hz 磁场暴露效应。
DOI：
10.1095/biolreprod55.2.455
复制
发表时间：
1996
影响因子：
3.6
通讯作者：
Yellon,SM
中科院分区：
文献类型：
--
作者：
Truong,H;Smith,JC;Yellon,SM
Photoperiodic regulation of the melatonin rhythm was studied in juvenile Djungarian hamsters to test the hypothesis that magnetic field (MF) exposures disrupt sexual maturation. Juveniles in long or short days postweaning were exposed each day to a 1-gauss 60-Hz MF (15 min, 2 h before lights-off). At age 25 days, nighttime duration of the melatonin rise in the pineal gland and circulation of sham-treated controls (adjacent coil system but without current) was < 8 h in long-day juveniles and nearly 13 h in short-day hamsters. This is the first study in juveniles to demonstrate that the melatonin rhythm duration is regulated by photoperiod and that reproductive development was not disrupted by daily or acute MF exposures; puberty was initiated in long days but arrested by short days, irrespective of MF treatment. In a replicate study, MF exposures had no effect on the duration of increased melatonin. In the initial and the replicate study, amplitude differences in the nighttime pineal or serum melatonin rise possibly reflected inherent variability in repetitive melatonin rhythms. In addition, effects of daily melatonin injections to arrest puberty were not blocked by daily MF exposures. The findings support the conclusion that MF exposures fail to disrupt photoperiodic time measurement or the neuroendocrine mechanism regulating reproductive maturation in the juvenile Djungarian hamster.
