Journal ArticleDOI
Comparisons of sizes of pinealocyte nuclei and pinealocytes in young and adult Chinese hamsters (Cricetulus griseus) under different photoperiod conditions.
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TLDR
In the Chinese hamster, the relationships between nuclear area and area of pinealocytes with time of day vary, depending on the age of animals as well as different photoperiodic conditions, although they differ only slightly.Abstract:
Semiquantitative electron microscopic observations on pinealocytes of the Chinese hamster (Cricetulus griseus) were made to compare the sizes of pinealocyte nuclei and pinealocytes as a whole, their nuclei and cytoplasm together, over a 24-hr period, between young animals (60-70 days old) and adult animals (120-130 days old) under LD 12:12 and between adults under LD 12:12 and LD 14:10. Under LD 12:12, similar 24-hr rhythms exist in the nuclear area and the area of pinealocytes of young animals, whereas in adults these values exhibit no significant 24-hr rhythm. In adults under LD 14:10, there is no significant 24-hr rhythm in the nuclear area, but the area of pinealocytes shows a statistically significant 24-hr rhythm. Thus, in the Chinese hamster, the relationships between nuclear area and area of pinealocytes with time of day vary, depending on the age of animals as well as different photoperiodic conditions, although they differ only slightly.read more
Citations
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Journal ArticleDOI
The ultrastructure of mammalian pinealocytes: a systematic investigation.
TL;DR: Whereas sufficient structural information now exists on cytoplasmic organelles such as synaptic ribbons and spherules, annulate lamellae, subsurface cisterns, and the several types of synaptic arrangements seen in relation to the pinealocyte soma and its processes, the functional role of these structures in pineal synthetic processes remains to be elucidated.
Journal ArticleDOI
The morpho-anatomy and histology of the pineal complex in a major Indian carp, Catla catla: identification of the pineal photoreceptor cells and their responsiveness to constant light and constant darkness during different phases of the annual reproductive cycle.
TL;DR: The apparent lack of any cellular responses either in the PS, or in the DS, following exposure to LL and DD, suggests that in C. catla the photoreceptor cells are located only within the epithelial lining of the EV and that these cells respond in a manner similar to mammalian pinealocytes when subjected to comparable photoperiod‐induced experimental conditions.
Journal ArticleDOI
The Structure of the Pineal Complex in a Common Indian Teleost, Catla catla: Evidence for Pineal‐Induced Inhibition of Testicular Function Within an Annual Reproductive Cycle
TL;DR: It was noted that both the nuclear diameter and the apical cytoplasmic projections of the EV photoreceptor cells showed a significant reduction, thus suggesting a reduced synthetic activity, during the month of July, the spawning phase of the reproductive cycle.
Journal ArticleDOI
Cytological studies of the pineal in relation to the annual cycles in the testis and climatological variables of free‐living roseringed parakeets (Psittacula krameri)
Saumen Kumar Maitra,Mamata Dey +1 more
TL;DR: Cytological studies of the pineal and the testes in free‐living roseringed parakeets show that the activities of both organs undergo definite annual changes.
Journal ArticleDOI
Quantitative light microscopic study on the heterogeneity in the superficial pineal gland of the rat
TL;DR: The previous results regarding regional and day‐night differences in pinealocyte size in rats are conflicting and the relationships between these differences and the vascularity and sympathetic innervation have scarcely been investigated.
References
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Journal ArticleDOI
Use of Ranks in One-Criterion Variance Analysis
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Journal ArticleDOI
The pineal gland of the gerbil, Meriones unguiculatus. II. Morphometric analysis over a 24-hour period.
TL;DR: A diurnal rhythm in the cellular volume of gerbil pinealocytes was determined and it is suggested that, although part of the secretory product of the pinealocyte may be present in dense-cored vesicle, other locations could include the free cytoplasm and clear secretory vesicles.
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