title: Effect of cortisol on gonadotropin inhibitory hormone (GnIH) in the cinnamon clownfish, Amphiprion melanopus.
abstract: Hypothalamic peptides, gonadotropin-releasing hormone (GnRH) and gonadotropin inhibitory hormone (GnIH), play pivotal roles in the control of reproduction and gonadal maturation in fish. In the present study we tested the possibility that stress-mediated reproductive dysfunction in teleost may involve changes in GnRH and GnIH activity. We studied expression of brain GnIH, GnIH-R, seabream GnRH (sbGnRH), as well as circulating levels of follicle stimulating hormone (FSH), and luteinizing hormone (LH) in the cinnamon clownfish, Amphiprion melanopus. Treatment with cortisol increased GnIH mRNA level, but reduced sbGnRH mRNA and circulating levels of LH and FSH in cinnamon clownfish. Using double immunofluorescence staining, we found expression of both GnIH and GnRH in the diencephalon region of cinnamon clownfish brain. These findings support the hypothesis that cortisol, an indicator of stress, affects reproduction, in part, by increasing GnIH in cinnamon clownfish which contributes to hypothalamic suppression of reproductive function in A. melanopus, a protandrous hermaphroditic fish.
authors.affiliation: Division of Marine BioScience, Korea Maritime and Ocean University, Busan 49112, Republic of Korea. Electronic address: discus62@kmou.ac.kr.
authors.forename: Young Jae
authors.initials: YJ
authors.lastname: Choi
authors.affiliation: Department of Biological Sciences, University of Calgary, Alberta T3B 2V4, Canada. Electronic address: habibi@ucalgary.ca.
authors.forename: Hamid R
authors.initials: HR
authors.lastname: Habibi
authors.affiliation: Division of Electrical and Electronic Engineering, Korea Maritime and Ocean University, Busan 49112, Republic of Korea. Electronic address: kilgs@kmou.ac.kr.
authors.forename: Gyung-Suk
authors.initials: GS
authors.lastname: Kil
authors.affiliation: Jeju Fisheries Research Institute, National Institute of Fisheries Science, Jeju 63068, Republic of Korea. Electronic address: jminmin@korea.kr.
authors.forename: Min-Min
authors.initials: MM
authors.lastname: Jung
authors.affiliation: Division of Marine BioScience, Korea Maritime and Ocean University, Busan 49112, Republic of Korea. Electronic address: choic@kmou.ac.kr.
authors.forename: Cheol Young
authors.initials: CY
authors.lastname: Choi
mesh_terms: D000818:Animals; D001921:Brain / Q000502:physiology; D005640:Follicle Stimulating Hormone / Q000097:blood; D018507:Gene Expression Regulation, Developmental; D007987:Gonadotropin-Releasing Hormone / Q000032:analysis / Q000235:genetics*; D006854:Hydrocortisone / Q000378:metabolism*; D007028:Hypothalamic Hormones / Q000032:analysis / Q000235:genetics*; D007986:Luteinizing Hormone / Q000097:blood; D010473:Perciformes / Q000097:blood / Q000235:genetics / Q000502:physiology*; D012333:RNA, Messenger / Q000235:genetics; D012098:Reproduction; D013312:Stress, Physiological
chemical_list: D007028:Hypothalamic Hormones; D012333:RNA, Messenger; D007987:Gonadotropin-Releasing Hormone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D006854:Hydrocortisone
keywords: Amphiprion melanopus; Cortisol; GnIH; Hypothalamic-pituitary-gonadal axis; Sexual maturation