Seasonal changes of plasma sex steroids in captive longtooth grouper Epinephelus bruneus (Bloch) in subtropical regions

2021 ◽  
Author(s):  
Shukei Masuma ◽  
Yuki Kusunoki ◽  
Ryuichiro Aoki
Keyword(s):  
Sex Steroids ◽  
Seasonal Changes ◽  
Epinephelus Bruneus

scholarly journals Melatonin Controls Photoperiodic Changes in Tanycyte Vimentin and Neural Cell Adhesion Molecule Expression in the Djungarian Hamster (Phodopus sungorus)

Endocrinology ◽  
2011 ◽  
Vol 152 (10) ◽  
pp. 3871-3883 ◽  
Author(s):  
Matei Bolborea ◽  
Marie-Pierre Laran-Chich ◽  
Kamontip Rasri ◽  
Herbert Hildebrandt ◽  
Piyarat Govitrapong ◽  
...  
Keyword(s):  
Cell Adhesion ◽  
Adhesion Molecule ◽  
Sex Steroids ◽  
Seasonal Changes ◽  
Cell Adhesion Molecule ◽  
Neural Cell Adhesion Molecule ◽  
Brain Plasticity ◽  
Neural Cell ◽  
Djungarian Hamster ◽  
Neural Cell Adhesion

The Djungarian hamster displays photoperiodic variations in gonadal size synchronized to the seasons by the nightly secretion of the pineal hormone melatonin. In short photoperiod (SP), the gonads regress in size, and circulating sex steroids levels decline. Thus, the brain is subject to seasonal variations of both melatonin and sex steroids. Tanycytes are specialized glial cells located in the ependymal lining of the third ventricle. They send processes either to the meninges or to blood vessels of the medio-basal hypothalamus. Furthermore, they are known to locally modulate GnRH release in the median eminence and to display seasonal structural changes. Seasonal changes in tanycyte morphology might be mediated either through melatonin or sex steroids. Therefore, we analyzed the effects of photoperiod, melatonin, and sex steroids 1) on tanycyte vimentin expression by immunohistochemistry and 2) on the expression of the neural cell adhesion molecule (NCAM) and polysialic acid as markers of brain plasticity. Vimentin immunostaining was reduced in tanycyte cell bodies and processes in SP. Similarly, tanycytes and their processes contained lower amounts of NCAM in SP. These changes induced by SP exposure could not be restored to long photoperiod (LP) levels by testosterone supplementation. Likewise, castration in LP did not affect tanycyte vimentin or NCAM expression. By contrast, late afternoon melatonin injections mimicking a SP-like melatonin peak in LP hamsters reduced vimentin and NCAM expression. Thus, the seasonal changes in vimentin and NCAM expression in tanycytes are regulated by melatonin independently of seasonal sex steroid changes.

Seasonal changes of serum sex steroids concentration and aromatase activity of gonad and brain in red-spotted grouper (Epinephelus akaara)

2007 ◽  
Vol 99 (1-2) ◽  
pp. 156-166 ◽  
Author(s):  
Guang-Li Li ◽  
Xiao-Chun Liu ◽  
Hao-Ran Lin
Keyword(s):  
Sex Steroids ◽  
Seasonal Changes ◽  
Aromatase Activity ◽  
Epinephelus Akaara

Seasonal Changes in Plasma Concentrations of Sex Steroids in the Salamander Hynobius nigrescens

1993 ◽  
Vol 90 (1) ◽  
pp. 51-57 ◽  
Author(s):  
Masato Hasumi ◽  
Hisaaki Iwasawa ◽  
Yoshitaka Nagahama
Keyword(s):  
Sex Steroids ◽  
Seasonal Changes ◽  
Plasma Concentrations

Aggression, body condition, and seasonal changes in sex-steroids in four hummingbird species

2014 ◽  
Vol 155 (4) ◽  
pp. 1017-1025 ◽  
Author(s):  
Paulina L. González-Gómez ◽  
William S. Blakeslee ◽  
Pablo Razeto-Barry ◽  
Rachel M. Borthwell ◽  
Sara M. Hiebert ◽  
...  
Keyword(s):  
Body Condition ◽  
Sex Steroids ◽  
Seasonal Changes

Seasonal changes of plasma gonadotropins and sex steroids in phasianus colchicus reared in outdoor cages

1984 ◽  
Vol 20 (6) ◽  
pp. 1569
Author(s):  
H. Sakai ◽  
S. Ishii ◽  
M. Sato ◽  
S. Wakabayashi
Keyword(s):  
Sex Steroids ◽  
Seasonal Changes ◽  
Phasianus Colchicus

Spreading the Word: Seasonal Changes Mean New Opportunities for Media Coverage

ASHA Leader ◽  
2013 ◽  
Vol 18 (7) ◽  
Keyword(s):  
Media Coverage ◽  
Seasonal Changes ◽  
Swimming Pools

Summer kicking into high gear conjures images of swimming pools and barbeques. But before you book your beach house for the weekend, think about what the changing seasons can mean for you professionally.

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