Probable effect of photoperiod on seasonal variation in the nuclear volume of the adrenal cortex of viscacha (Lagostomus maximus maximus)
| Autor: | M. Delgado, Guzmán Ja, A.C. Ribes, Fabian Mohamed, Ramón S. Piezzi, Luis Scardapane, Servando Álvarez Domínguez |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 1999 |
| Předmět: |
Male
medicine.medical_specialty endocrine system food.ingredient Physiology media_common.quotation_subject Immunology Biophysics Rodentia viscacha (Lagostomus maximus maximus) melatonin photoperiod Biochemistry Melatonin food Internal medicine fasciculata medicine Animals General Pharmacology Toxicology and Pharmaceutics lcsh:QH301-705.5 media_common photoperiodism Lagostomus lcsh:R5-920 biology Adrenal cortex General Neuroscience Cell Biology General Medicine Viscacha biology.organism_classification glomerulosa reticularis Endocrinology medicine.anatomical_structure adrenal lcsh:Biology (General) Adrenal Cortex Seasons Zona Fasciculata Reproduction lcsh:Medicine (General) Nucleus Zona reticularis morphometry medicine.drug |
| Zdroj: | Brazilian Journal of Medical and Biological Research, Vol 32, Iss 9, Pp 1115-1120 (1999) Brazilian Journal of Medical and Biological Research, Volume: 32, Issue: 9, Pages: 1115-1120, Published: SEP 1999 Brazilian Journal of Medical and Biological Research v.32 n.9 1999 Brazilian Journal of Medical and Biological Research Associação Brasileira de Divulgação Científica (ABDC) instacron:ABDC |
| ISSN: | 0034-7310 |
| Popis: | The neuroendocrine system regulates several organic functions such as reproduction, metabolism and adaptation to the environment. This system shows seasonal changes linked to the environment. The experimental model used in the present study was Lagostomus maximus maximus (viscacha). The reproduction of males of this species is photoperiod dependent. Twenty-four adult male viscachas were captured in their habitat at different times during one year. The adrenal glands were processed for light microscopy. Serial cuts were stained with hematoxylin-eosin for the morphometric study, and 100 nuclei of each zone of the adrenal cortex were counted per animal. Data were analyzed statistically by ANOVA and the Tukey test. The cells of the glomerulosa zone are arranged in a tube-shaped structure. The fasciculata zone has large cells with central nuclei and clearly visible nucleoli and with a vacuolar cytoplasm. In the reticularis zone there are two of types of cells, one with a nucleus of fine chromatin and a clearly visible nucleolus and the other with nuclear pycnosis. Morphometric analysis showed maximum nuclear volumes during the February-March period with values of 133 +/- 7.3 microm3 for the glomerulosa, 286.4 +/- 14.72 microm3 for the fasciculata, and 126.3 +/- 9.49 microm3 for the reticularis. Minimum nuclear volumes were observed in August with values of 88.24 +/- 9.9 microm3 for the glomerulosa, 163.7 +/- 7.78 microm3 for the fasciculata and 64.58 +/- 4.53 microm3 for the reticularis. The short winter photoperiod to which viscacha is subjected could inhibit the adrenal cortex through a melatonin increase which reduces the nuclear volume as well as the cellular activity. |
| Databáze: | OpenAIRE |
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