The environmental regulation of maturation in goldfish, Carassius auratus: effects of various LED light spectra.
While there have been a number of studies on the effects of photoperiod and duration of light and dark exposure, much less information is available on the importance of light intensity. This study investigated the effects of exposure of goldfish, Carassius auratus exposed to white fluorescent bulbs, and red (peak at 630nm), and green (530nm) light emitting diodes (LEDs) at approximately 0.9W/m(2) (12-h light:12-h dark) for four months on a number of hormones of the hypothalamus-pituitary-gonad (HPG) axis, in vivo and in vitro. We investigated the effects of native GnRH molecules (gonadotropin-releasing hormones; salmon GnRH, sGnRH; and chicken GnRH-II, cGnRH-II), gonadotropin hormones (GTHα; follicle-stimulating hormone, FSH-β; luteinizing hormone, LH-β2), kisspeptin 1 (Kiss1) and G protein-coupled receptor 54 (GPR54) mRNA levels. Furthermore, we measured LH and 17α-hydroxypregnenolone levels in plasma and we performed gonad histological observations. GnRHs, Kiss1, GPR54 and GTH mRNA and plasma LH and 17α-hydroxypregnenolone levels in the in vivo and in vitro groups exposed to green LEDs were significantly higher than the other groups. Histological analysis revealed the presence of oocytes in the yolk stage in fish exposed to green light. These results suggest that green wavelengths regulate the HPG axis and enhance sexual maturation in goldfish.
Division of Marine Environment & BioScience, Korea Maritime and Ocean University, Busan 606-791, Republic of Korea.
Hyun Suk
HS
Shin
Department of Biological Sciences, University of Calgary, 2500 University Drive N.W. Calgary, Alberta T3B 2V4, Canada. Electronic address: habibi@ucalgary.ca.
Hamid R
HR
Habibi
Division of Marine Environment & BioScience, Korea Maritime and Ocean University, Busan 606-791, Republic of Korea. Electronic address: choic@kmou.ac.kr.
Cheol Young
CY
Choi
D006907:17-alpha-Hydroxypregnenolone / Q000097:blood; D000818:Animals; D002478:Cells, Cultured; D005260:Female; D029941:Fish Proteins / Q000097:blood / Q000235:genetics; D015870:Gene Expression; D006054:Goldfish / Q000254:growth & development*; D007987:Gonadotropin-Releasing Hormone / Q000502:physiology; D006062:Gonadotropins / Q000097:blood; D048788:Growth and Development / Q000528:radiation effects; D007030:Hypothalamo-Hypophyseal System; D007031:Hypothalamus / Q000166:cytology / Q000378:metabolism; D059648:Kisspeptins / Q000097:blood / Q000235:genetics; D008027:Light; D007986:Luteinizing Hormone / Q000097:blood; D010053:Ovary / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*; D044088:Receptors, Galanin / Q000235:genetics / Q000378:metabolism
D029941:Fish Proteins; D006062:Gonadotropins; D059648:Kisspeptins; D044088:Receptors, Galanin; D007987:Gonadotropin-Releasing Hormone; D006907:17-alpha-Hydroxypregnenolone; D007986:Luteinizing Hormone
Gonadotropin hormone; Gonadotropin-releasing hormone; Hypothalamus–pituitary–gonad; Kisspeptin; Light emitting diodes; Sexual maturation