| molecular cloning of kisspeptin receptor genes (gpr54-1 and gpr54-2) and their expression profiles in the brain of a tropical damselfish during different gonadal stages. | the kisspeptin receptor (gpr54) mediates neuroendocrine control of kisspeptin in the brain and acts as a gateway for a pulsatile release of hypothalamic gonadotropin-releasing hormone. this study aimed to clone two gpr54 genes (gpr54-1 and gpr54-2) from the brain of the sapphire devil chrysiptera cyanea, a tropical damselfish, and to study their involvement in reproduction. the partial sequences of the sapphire devil gpr54-1 cdna (1059bp) and gpr54-2 cdna (1098bp) each had an open reading frame ... | 2017 | 27475299 |
| existence of a photoinducible phase for ovarian development and photoperiod-related alteration of clock gene expression in a damselfish. | the sapphire devil, chrysiptera cyanea, is a reef-associated damselfish and their ovarian development can be induced by a long photoperiod. in this study, we demonstrated the existence of a photoinducible phase for the photoperiodic ovarian development in the sapphire devil. induction of ovarian development under night-interruption light schedules and nanda-hamner cycles revealed that the photoinducible phase appeared in a circadian manner between zt12 and zt13. to characterize the effect of pho ... | 2015 | 26093172 |
| effects of neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (mptp) treatment on ovarian development of the sapphire devil, chrysiptera cyanea. | in the neuroendocrine system controlling fish reproduction, dopamine (da) acts as a gonadotropin inhibitory factor and plays a role in regulating gonadal development of certain species. the present study examined the effects of chemical destruction of dopaminergic neurons in the brain on da production and ovarian development in the sapphire devil chrysiptera cyanea, a reef-associated damselfish. the avidin-biotin-peroxidase complex method using an antibody against tyrosine hydroxylase (th), a cr ... | 2015 | 25362562 |
| effects of different colors of light on melatonin suppression and expression analysis of aanat1 and melanopsin in the eye of a tropical damselfish. | ocular melatonin production exhibits a daily rhythm with a decrease during photophase and an increase during scotophase (nocturnal pattern) in teleost fish due to day-night changes in the activity of the rate-limiting melatonin synthesizing enzyme arylalkylamine n-acetyltransferase (aanat). acute light exposure during scotophase suppresses aanat activity and melatonin production in the eyes, suggesting that external light signals are a principal regulator of ocular melatonin synthesis. to better ... | 2014 | 24859252 |
| possible roles of photoperiod and melatonin in reproductive activity via changes in dopaminergic activity in the brain of a tropical damselfish, chrysiptera cyanea. | the perception of periodical change in photoperiodic conditions by photosensory organs is the first step to initiating reproductive activity in fish. to date, it is not known how photoperiodic cues are endogenously transduced to the endocrine network of the brain-pituitary-gonad axis after the perception of photoperiodic stimuli. because dopamine (da) inhibits gonadotropin release from the pituitary in certain teleosts, it is likely that it is a key mediator of photoperiodic stimulation. we exam ... | 2013 | 24090612 |
| molecular cloning and expression of long-wavelength-sensitive cone opsin in the brain of a tropical damselfish. | ovarian development of the sapphire devil, chrysiptera cyanea, exhibits photoperiodism and is stimulated under long-day conditions. previous studies suggest that red light is more effective than green and blue lights for inducing ovarian development. in addition, the extra-retinal photoreception involved in the ovarian development is suggested in this species. the present study aimed to clone the red-light-sensitive cone opsin (sdlws) of this species, to demonstrate its expression in the brain, ... | 2011 | 21871576 |
| action of melanin-concentrating hormone (mch) on teleost chromatophores. | the in vitro effects of synthetic salmon melanin-concentrating hormone (mch) on chromatophores of four teleost species were studied. in the erythrophores of the platyfish (xiphophorus maculatus) and the swordtail (xiphophorus helleri), and in the xanthophores and amelanotic melanophores of the medaka (oryzias latipes), pigment aggregation took place in response to mch even in the absence of ca2+. in contrast to this, the leucophores of the medaka responded to mch by the pigment dispersion but on ... | 1986 | 3026881 |
| cyclic nucleotide action is mediated through adenosine receptors in damselfish motile iridophores. | effects of cyclic nucleotides on motile iridophores were examined in the blue damselfish, chrysiptera cyanea. all of the cyclic nucleotides tested, i.e. camp, 2',3'-camp and cgmp, accelerated the clearing response of the cells even at concentrations of 10(-5) or 10(-4) m. the action of these nucleotides was effectively antagonized by methylxanthines. these results suggest that the effect of cyclic nucleotides on damselfish iridophores is mediated by adenosine receptors in a similar fashion to th ... | 1986 | 2877810 |
| melanin concentrating hormone (mch) effects on teleost (chrysiptera cyanea) melanophores. | the in vitro biological actions of synthetic chum salmon melanin concentrating hormone (mch) on melanophores of the blue damselfish (a teleost), chrysiptera cyanea, were studied. this cyclic heptadecapeptide stimulated melanosome (melanin granule) aggregation (centripetal migration) within melanophores at a threshold concentration of about 10(-10) m. the action of this putative hormone was not blocked by alpha- or beta-adrenoceptor antagonists. it was concluded that the effects of mch were direc ... | 1985 | 4056687 |
| control of chromatophore movements in dermal chromatic units of blue damselfish--i. the melanophore. | mechanisms controlling pigment movements in the melanophore of the blue damselfish, chrysiptera cyanea, were studied. histological observations revealed that the melanophore had three-dimensionally developed processes to envelop overlying small iridophores, and thus participated in the construction of a simple dermal chromatophore unit. nervous stimulation, catecholamines and melatonin brought about melanosome aggregation in the melanophore. the actions of the nervous stimulation and catecholami ... | 1985 | 2861944 |