Abstract：
:Plasma profiles of several gonadal steroids and cortisol were examined in a field population of the protandrous, sex-changing anemonefish Amphiprion melanopus to elucidate potential roles of these hormones in gonadal sex change. Sex change was experimentally induced in males by removal of their dominant female pair mates. These sex-changing males were captured and sampled at 5, 10, or 20 days after female removal. Unmanipulated males and females were also sampled. Males had higher plasma levels of 11-ketotestosterone (11-KT) than did females, but had lower levels of androstenedione (Ad), testosterone (T), and estradiol-17 beta (E2). The three androgens showed decreases from male levels at 10 days, then an increasing trend at 20 days after female removal. E2 levels exhibited no changes from male levels until 20 days, when a significant increase over male levels was observed. Mature females had higher levels of Ad, T, and E2 than the 20-day treatment group, indicating that these steroids continue to rise after Day 20. The results support hypothesized roles for androgens in male function and E2 in female function in A. melanopus. However, E2 increases lagged behind oogonial proliferation, arguing against an influence of this steroid in the initiation of female function. Cortisol levels did not differ between males and females, but exhibited an increase during sex change, peaking at 20 days.
journal_name
Gen Comp Endocrinoljournal_title
General and comparative endocrinologyauthors
Godwin JR,Thomas Pdoi
10.1006/gcen.1993.1114subject
Has Abstractpub_date
1993-08-01 00:00:00pages
144-57issue
2eissn
0016-6480issn
1095-6840pii
S0016-6480(83)71114-7journal_volume
91pub_type
杂志文章abstract：:Two forms of immunoreactive gonadotropin-releasing hormone (GnRH) were extracted from brain-pituitary tissues of Thai catfish, Clarias macrocephalus and C. batrachus. The peptides were detected using high performance liquid chromatography (HPLC) and radioimmunoassay (RIA). In both the HPLC systems, catfish GnRH-I elut...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(92)90031-e
更新日期：1992-08-01 00:00:00
abstract：:Molecular cloning of thyrotropin-releasing hormone receptors (TRHR) was performed in a teleost, the sockeye salmon (Oncorhynchus nerka). Four different TRHR cDNAs were cloned and named TRHR1, TRHR2a, TRHR2b and TRHR3 based on their similarity to known TRHR subtypes in vertebrates. Important residues for TRH binding we...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2011.07.011
更新日期：2011-11-01 00:00:00
abstract：:The investigation of calcitonin-like immunoreactivity performed in whole extracts of the terrestrial crustacean Orchestia cavimana using radioimmunoassay revealed large amounts of these peptides varying in concentration according to the stages of the molt cycle. Their level is maximum at the time of the exuviation. Th...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(89)90057-9
更新日期：1989-01-01 00:00:00
abstract：:This study investigates the effects of exogenous thyroxine (T4) on running endurance, tissue masses, and the activities of citrate synthase (CS), pyruvate kinase (PK), cytosolic alpha-glycerophosphate dehydrogenase (alpha-GPDH), and beta-hydroxyacyl Coenzyme A dehydrogenase (HOAD) in Sceloporus undulatus (eastern fenc...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(91)90132-p
更新日期：1991-01-01 00:00:00
abstract：:In adult domestic fowl, angiotensin (ANG) receptors are present in the vascular smooth muscles (VSM) and in the endothelium, mediating vasorelaxation via endothelium-derived relaxing factor/cGMP. ANG II-induced relaxation is minor in chicks and becomes more marked as they mature but diminishes in adult birds, whereas ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1998.7150
更新日期：1998-10-01 00:00:00
abstract：:The corticosterone response to the sight of a natural predator was investigated in free-living and captive great tits (Parus major). Free-living great tits responded to the sight of a stuffed, slowly moving Tengmalm's owl, a major predator of great tits, with warning calls and a change in behaviour around a feeder. Gr...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.2001.7749
更新日期：2002-02-01 00:00:00
abstract：:To examine the reproductive endocrinology of a large pleuronectiform fish, barfin flounder, Verasper moseri, a promising candidate for aquaculture and resource enhancement in northern Japan due to its high commercial value, three gonadotropin-releasing hormones (GnRHs) in the brain was identified by isolation of their...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/s0016-6480(02)00008-4
更新日期：2002-05-01 00:00:00
abstract：:The role of cyclic AMP (cAMP) as mediator of ACTH action on interrenal steroidogenesis was evaluated in juvenile coho salmon (Oncorhynchus kisutch). Head kidneys (containing the interrenal cells) were incubated in the absence or presence of putative adenylate cyclase activators (forskolin and cholera toxin), ACTH comb...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(86)90160-7
更新日期：1986-08-01 00:00:00
abstract：:Isospecific injections of intercerebral commissure (COM) extracts of L. stagnalis, L. palustris, and L. ovata (Lymnaeidae) and of extracts of COM/mediodorsal bodies complexes (COM/DB) of Bulinus truncatus (Bulinidae) and Biomphalaria glabrata (Planorbidae) induced oviposition in a high percentage of the experimental s...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(83)90164-8
更新日期：1983-10-01 00:00:00
abstract：:Rhythmic synthesis of moulting hormones (ecdysteroids) by prothoracic glands (PGs) of the insect Rhodnius prolixus during the last larval instar was studied in vitro following explantations every 4-5 hr for up to 96 hr. Ecdysteroid synthesis was measured by radioimmunoassay as the quantity of ecdysteroid produced duri...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(91)90102-c
更新日期：1991-07-01 00:00:00
abstract：:Four genomes and two transcriptomes from six Chelicerate species were analyzed for the presence of neuropeptide and neurohormone precursors and their GPCRs. The genome from the spider Stegodyphus mimosarum yielded 87 neuropeptide precursors and 101 neuropeptide GPCRs. High neuropeptide transcripts were also found in t...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2015.07.014
更新日期：2016-11-09 00:00:00
abstract：:The growth hormone (GH) gene has been characterized for a number of fishes and used to establish phylogenetic relationships and as a candidate gene for studies of genetic variation in connection with growth traits. In this study, we report the genomic structure of Nibea coibor GH (designated as ncGH) including its 5'-...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2009.03.030
更新日期：2009-09-15 00:00:00
abstract：:Previous data have shown that regional differences in the presence of anterior pituitary luteinizing hormone (LH) generally correlate with the comparable disparities in distribution of gonadotropes throughout the gland. In female rats, the differences are apparent over the estrous cycle, but are more prominent during ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2008.02.015
更新日期：2008-05-01 00:00:00
abstract：:Oligonucleotide probes were synthesized for the mRNAs of a pair of tilapia prolactins (tPRL177 and tPRL188) and growth hormone (tGH) based on cDNAs for the hormones of Oreochromis niloticus and amino acid sequences for the hormones of O. mossambicus. The three 45mer probes were labeled with 35S for hybridization studi...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1993.1010
更新日期：1993-01-01 00:00:00
abstract：:A radioimmunoassay (RIA) capable of determining blood ACTH levels in salmonid fishes was developed and validated. The RIA used an antibody raised against mammalian ACTH, iodinated human ACTH as tracer, and human 1-39 ACTH as standard. Incubation of the standard or unknown with antibody for 3 days before addition of as...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(86)90046-8
更新日期：1986-06-01 00:00:00
abstract：:Unlike mammals, the goldfish is unique in having dopamine (DA) D1 receptors in the anterior pituitary. In this species, DA stimulates growth hormone (GH) release via D1 receptors coupled to the cAMP-dependent pathway. To further examine the postreceptor mechanisms of this novel pituitary DA D1 system, the role of extr...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1994.1088
更新日期：1994-06-01 00:00:00
abstract：:Owl clutches typically hatch asynchronously, and brood size hierarchies develop. In this study, we describe intra-clutch variation of testosterone, androstenedione, estradiol, and corticosterone in Eastern screech owl egg yolks. In order to assess whether these hormones may have originated in the follicle, we also cha...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2011.04.001
更新日期：2011-07-01 00:00:00
abstract：:Endocrine cells in the gut of Sparus auratus L. (gilt-head sea bream) have been demonstrated by immunocytochemical and electron microscopic techniques. Cells showing somatostatin and gastrin-like immunoreactivity were found in the depth of the gastric folds and in the upper part of the stomach glands while substance P...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(86)90067-5
更新日期：1986-12-01 00:00:00
abstract：:The presence of cholecystokinin (CCK), originally isolated from porcine small intestine, has been reported in a diversity of invertebrates ranging, from cnidarians to protochordates, but so far, not in echinoderms. We have used immunohistochemical techniques to demonstrate the presence of cells expressing CCK-like imm...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(91)90026-3
更新日期：1991-08-01 00:00:00
abstract：:In bony fishes, both corticotropin-releasing factor (CRF) and urotensin-I play a role in the regulation of interrenal glucocorticoid release. The rainbow trout, Oncorhynchus mykiss, is a useful model for understanding the mechanisms of stress and the hypothalamo-pituitary-interrenal axis because of its phylogenetic po...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1999.7290
更新日期：1999-08-01 00:00:00
abstract：:Melatonin and arylalkylamine N-acetyltransferase (AANAT), the rate-limiting enzyme in melatonin synthesis, have taken on special importance in vertebrate circadian biology. Recent identification of genes encoding two AANAT (AANAT(1) and AANAT(2)) and two subtypes of melatonin receptor (Mel-R; Mel(1a) and Mel(1b)) in s...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2004.01.004
更新日期：2004-05-01 00:00:00
abstract：:The present paper describes neuropeptide Y-like-immunoreactive (NPY-ir) structures in the brain of the spotted gar, Lepisosteus oculatus, with special regard to their anatomical relations to gonadotropin-releasing hormone (GnRH)-ir structures in the hypothalamus and the terminal nerve (TN). NPY-ir cells were found in ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2005.02.010
更新日期：2005-07-01 00:00:00
abstract：:Our previous study demonstrated that recombinant goldfish activin B stimulated goldfish FSHbeta but inhibited LHbeta expression. Similar to activin B, activin A also exhibited the inverse effects on the expression of the two gonadotropins. The novel dual effects of activins on FSH and LH in the goldfish raise an inter...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2003.08.012
更新日期：2004-01-01 00:00:00
abstract：:Effects of growth hormone (GH) on the synthesis of mucopolysaccharide by ceratobranchial cartilages of the Japanese eel, Anguilla japonica, were examined by monitoring the in vitro uptake of [35S]sulfate. The [35S]sulfate uptake decreased rapidly to one-third of the initial level during the first 3 days after hypophys...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(90)90117-5
更新日期：1990-08-01 00:00:00
abstract：:Seasonal patterns of fecal 17beta-OH-androgen, estrogen, and progesterone equivalents of male and female greylag geese (Anser anser) were analyzed in a flock of free-living geese. These were compared among social categories determined by pairbond status and breeding success. The annual cycle was divided into 13 phases...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1998.7236
更新日期：1999-04-01 00:00:00
abstract：:The growth hormone (Gh)/insulin-like growth-factor (Igf) system plays a central role in the regulation of growth in fishes. However, the roles of Igf binding proteins (Igfbps) in coordinating responses to food availability are unresolved, especially in anadromous fishes preparing for seaward migration. We assayed plas...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2016.05.015
更新日期：2016-07-01 00:00:00
abstract：:In mammals ghrelin has a diverse range of effects including stimulation of gut motility but although present in teleost fish its effects on motility have not been investigated. The present study used bioinformatics to search for fish paralogues of the ghrelin receptor and the closely related motilin receptor, and inve...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2007.05.016
更新日期：2008-01-01 00:00:00
abstract：:The endocrine pancreas of the lizard Podarcis hispanica is described using light and electron microscopy. The endocrine pancreas of this reptile is located throughout the spleen side of the organ and consists of islet-like structures, small groups of two to five cells, and single scattered endocrine cells. The endocri...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(88)90250-x
更新日期：1988-08-01 00:00:00
abstract：:Plasma glucocorticoid (CORT) levels collected within 3min of capture are commonly believed to reflect pre-stressor, baseline CORT levels. Differences in these "baseline" values are often interpreted as reflecting differences in health, or the amount of social and environmental stress recently experienced by an individ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2017.01.028
更新日期：2017-06-01 00:00:00
abstract：:The majority of birds use environmental cues to time their reproduction. Photoperiod is the most dominant cue, but other environmental factors may play a critical role in successful reproduction. Some previous studies show the effect of temperature on the timing of nest building and reproduction. Here we tested if the...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2020.113654
更新日期：2021-01-15 00:00:00
