Abstract:
:Although pineal "synaptic" ribbons (SR) are frequently examined by means of quantitative electron microscopy, their functional significance remains unclear. The same is true for related structures--"synaptic" spherules (SPH). In the course of such studies, it has been noted that SR counts may differ from laboratory to laboratory. Because seasonal changes may play a role, a 2-year study was performed on male rats kept under routine laboratory conditions and killed at monthly intervals during daytime or nighttime. Both structures examined showed distinct day-night differences throughout the year, with higher numbers at night than during the day. There were significant annual changes in both SR and SPH during both daytime and nighttime. The comparison of the curves from the 2 years showed that they were virtually identical both during daytime and nighttime. The numbers of SR were the highest in October and the lowest in April; the numbers of SPH had two plateaus, one with lower values from November to April, and the other with higher values from May to October. It appears from the present study that SR and SPH numbers in the rat pineal gland show statistically significant and precisely timed seasonal changes that may well account for the variations of SR numbers in the different publications.
journal_name
J Biol Rhythmsjournal_title
Journal of biological rhythmsauthors
Karasek M,Lewinski A,Vollrath Ldoi
10.1177/074873048800300103subject
Has Abstractpub_date
1988-04-01 00:00:00pages
41-8issue
1eissn
0748-7304issn
1552-4531journal_volume
3pub_type
杂志文章abstract::Siberian hamsters transferred from a long (16 h light/day [16 L]) to an intermediate (13.5 L) day length (DL) undergo testicular regression within 2 months followed approximately 2 months later by "spontaneous" testicular recrudescence. Recovery of gonadal function after prolonged exposure to intermediate DLs is thoug...
journal_title:Journal of biological rhythms
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doi:10.1177/074873002129002645
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journal_title:Journal of biological rhythms
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journal_title:Journal of biological rhythms
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journal_title:Journal of biological rhythms
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journal_title:Journal of biological rhythms
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journal_title:Journal of biological rhythms
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journal_title:Journal of biological rhythms
pub_type: 杂志文章,评审
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更新日期:2009-10-01 00:00:00
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journal_title:Journal of biological rhythms
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更新日期:2012-02-01 00:00:00
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journal_title:Journal of biological rhythms
pub_type: 杂志文章
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journal_title:Journal of biological rhythms
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journal_title:Journal of biological rhythms
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journal_title:Journal of biological rhythms
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journal_title:Journal of biological rhythms
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更新日期:1990-04-01 00:00:00
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journal_title:Journal of biological rhythms
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journal_title:Journal of biological rhythms
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journal_title:Journal of biological rhythms
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