Abstract：
:The effects of serotonin (5-HT) on gonadotropin and growth hormone release from perifused goldfish (Carassius auratus, L.) pituitary glands were studied. Serotonin, at micromolar concentrations, caused a dose-related release of gonadotropin and an inhibition of growth hormone release in pituitaries from goldfish at different sexual stages. At lower concentrations 5-HT continued to inhibit growth hormone release, but had no effects on gonadotropin release. The stimulatory effects of 5-HT on gonadotropin release could be blocked by ketanserin and cyproheptadine; however, these two antagonists had no effects on 5-HT inhibition of growth hormone release. Perifusion with melatonin had no effect on the release of gonadotropin or growth hormone release. These results demonstrate that 5-HT has a stimulatory effect on gonadotropin secretion, probably through a 5-HT2 receptor type, and an inhibitory effect on growth hormone through an unidentified receptor type. We hypothesize that the effects on gonadotropin release are due to direct actions on gonadotrophs, whereas the effects on growth hormone release may be due to stimulation of somatostatin release from neurosecretory terminals in the pituitary.
journal_name
Gen Comp Endocrinoljournal_title
General and comparative endocrinologyauthors
Somoza GM,Peter REdoi
10.1016/0016-6480(91)90301-lsubject
Has Abstractpub_date
1991-04-01 00:00:00pages
103-10issue
1eissn
0016-6480issn
1095-6840pii
0016-6480(91)90301-Ljournal_volume
82pub_type
杂志文章abstract：:The control of oocyte growth and its final maturation is multifactorial and involves a number of hypothalamic, hypophyseal, and peripheral hormones. In this study, we investigated the direct actions of the gonadotropin-releasing hormone (GnRH) and the gonadotropin-inhibitory hormone (GnIH), which are expressed in the ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2020.113619
更新日期：2020-12-01 00:00:00
abstract：:Using frog ovarian follicles in vitro we assessed the role of the theca/epithelium (THEP) layer and granulosa cells in the production of steroids. The THEP layer and granulosa cell-enclosed oocytes (GCEOs) were separated from ovarian follicles of the frog, Rana nigromaculata, by microdissection. Intact follicles (IFs)...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1994.1077
更新日期：1994-05-01 00:00:00
abstract：:Gonadotropin-inhibitory hormone (GnIH) is an inhibitor of the hypothalamic-pituitary-gonadal (HPG) axis. GnIH is also called RFamide-related peptide (RFRP) as GnIH peptides have a characteristic C-terminal LPXRFiamide (X = L or Q) sequence. GnIH is thought to be the mediator of stress by negatively regulating the HPG ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
doi：10.1016/j.ygcen.2018.03.004
更新日期：2018-09-01 00:00:00
abstract：:Aromatase is a key regulator of circulating testosterone (T) and 17-β-oestradiol (E2), two steroids which are critical to the development, maintenance and function of reproductive tissues. The role of aromatase in sexual differentiation in oviparous (egg-laying) reptiles is well understood, yet has never been explored...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2014.02.020
更新日期：2014-05-01 00:00:00
abstract：:Plasma prolactin (PRL) and vitellogenin (VTG) concentrations were determined during the annual reproductive cycle of the newt Triturus carnifex Laur. Plasma PRL was measured by a radioimmunoassay using purified newt (Cynops pyrrogaster) PRL as standard and radioligand and its antibodies. Using ELISA, plasma VTG titers...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1994.1132
更新日期：1994-09-01 00:00:00
abstract：:The presence of multiple forms of gonadotropin-releasing hormone (GnRH) within a single brain is common among vertebrate species. In previous studies of reptiles, two forms of GnRH were isolated from the brain of alligators and the primary structure was determined to be that of chicken (c)GnRH-I and cGnRH-II. GnRH has...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1997.6970
更新日期：1997-11-01 00:00:00
abstract：:Pinealectomized and intact chicks raised under cyclic (14L:10D) and noncyclic (OL;24L) conditions of environmental lighting were sampled 60 hr and 6 weeks after pinealectomy to evaluate the effects of pineal ablation on plasma and ocular melatonin concentrations. Little or no immunoreactive melatonin was present in pl...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(85)90114-5
更新日期：1985-06-01 00:00:00
abstract：:Measurement of fish steroids in water provides a non-invasive alternative to measurement in blood samples, offering the following advantages: zero or minimal intervention (i.e. no anaesthetic, bleeding or handling stress); results not being biased by sampling stress; repeat measurements on the same fish; the possibili...
journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
doi：10.1016/j.ygcen.2006.11.006
更新日期：2007-08-01 00:00:00
abstract：:Reptilia is the only vertebrate class in which cDNA for the gonadotropin beta subunit precursor molecule has not been cloned. We have isolated the full-length cDNA clone encoding the LH beta subunit precursor molecule and a partial cDNA clone encoding the FSH beta subunit precursor molecule from a pituitary cDNA libra...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/s0016-6480(03)00103-5
更新日期：2003-07-01 00:00:00
abstract：:The distribution and identity of the various endocrine cell types were examined in the pancreas, stomach, and anterior intestine of the phylogenetically ancient actinopterygian, the gar (Lepisosteus osseus L.), using immunohistochemistry. Antisera used were directed against several insulins (INSs) and somatostatins (S...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1996.6842
更新日期：1997-04-01 00:00:00
abstract：:The insulin receptors of frog brain and liver show features typical of other insulin receptors with regard to affinity and specificity of binding to insulins and proinsulin, solubility in Triton X-100, binding to and elution from wheat germ agglutinin, and insulin-sensitive tyrosine kinase activity. Likewise, the brai...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(87)90026-8
更新日期：1987-11-01 00:00:00
abstract：:Birds may react to the presence of humans with an immediate primary behavioural reaction and with physiological responses, such as the activation of the hypothalamo-pituitary-adrenal axis. This study investigates the suite of behavioural and adrenocortical responses to the presence of humans and to handling in two sub...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2006.02.012
更新日期：2006-09-01 00:00:00
abstract：:In the current study we investigated the interaction of hypothalamic paraventricular nucleus (PVN) glucagon-like peptide-1 (GLP-1) and ghrelin signaling in the control of metabolic function. We first demonstrated that acylated ghrelin injected directly into the PVN reliably altered the respiratory exchange ratio (RER)...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2018.10.008
更新日期：2019-01-01 00:00:00
abstract：:Endothelin (ET)-1 and suppressor of cytokine signaling (SOCS)-3 were respectively found to regulate energy metabolism and hormone signaling in fat cells. Although ET-1 can also regulate the expression of SOCS-3-stimulating hormones, it is still unknown whether ET-1 regulates SOCS-3 gene expression. This study investig...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2012.06.024
更新日期：2012-09-15 00:00:00
abstract：:During the previtellogenic development of mosquito fat body cells, the nucleolus, the organelle responsible for producing ribosomes, enlarges threefold, reaching maximal size between 2 and 3 days after eclosion. The granular component of the nucleolus containing ribosomal precursors increases considerably as well. The...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(90)90233-c
更新日期：1990-03-01 00:00:00
abstract：:The vasoconstrictive and cardiovascular actions of a recently identified bradykinin (BK)-related peptide (Gly-Ile-Thr-Ser-Trp-Leu-Pro-Phe) from the little skate, Leucoraja erinacea were examined in the unanesthetised little skate. Intra-arterial administration of a skate BK (0.1-1 nmolkg(-1)) produced a hypertensive r...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2011.08.002
更新日期：2011-11-01 00:00:00
abstract：:Pregnant female spiny dogfish were captured off the coasts of Maine and Massachusetts and morphometric and gravimetric analyses of the liver, gonad, and reproductive tract correlated with the reproductive cycle. Plasma samples were taken and circulating steroids (progesterone, testosterone, and estradiol) were measure...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(87)90266-8
更新日期：1987-05-01 00:00:00
abstract：:The gross morphology, histology, and ultrastructure of the thyroid gland of the koala, Phascolarctos cinereus, is described. Generally, the glands were found to contain large-diameter follicles in association with an epithelium of low height. Morphometric analysis demonstrated a high relative thyroid weight (0.3 +/- 0...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1998.7076
更新日期：1998-06-01 00:00:00
abstract：:The insulin-like growth factor (IGF) system in teleosts consists of two ligands, IGF-I and IGF-II, multiple binding proteins, and high-affinity transmembrane receptors. There exists a large gap in our knowledge of the structure and expression of receptors mediating the biological effects of the IGFs in teleosts. For e...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1999.7311
更新日期：1999-08-01 00:00:00
abstract：:Chickens have blood glucose concentrations that are twofold higher than those observed in mammals. Moreover, the insulin sensitivity seems to decrease with postnatal age in both broiler and layer chickens. However, little is known about the response of insulin on plasma glucose concentrations and mRNA abundance of hep...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2015.12.026
更新日期：2016-06-01 00:00:00
abstract：:Interference in radioimmunoassays (RIAs) was frequently encountered during endocrinological studies of the emu (Dromaius novaehollandiae). Interference was greatest when serum was cloudy or opaque. Such samples appeared seasonally, in spring and summer during the phase of fat deposition, and in the winter when females...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/s0016-6480(03)00088-1
更新日期：2003-06-15 00:00:00
abstract：:The present work describes the neuroanatomical distribution of the immunoreactive luteinizing hormone-releasing hormone (ir-LHRH) system in the brain of adult male and female, castrated male and developing Rana esculenta. No obvious sex differences in the distribution pattern of ir-LHRH were observed. Immunoreactive n...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(90)90033-i
更新日期：1990-06-01 00:00:00
abstract：:Changes in the pituitary cells involved in amphibian metamorphosis were studied in Bufo arenarum tadpoles with inhibited thyroid function. After hatching, larvae were treated for 5 months with potassium perchlorate (KClO4), a goitrogenic substance known to prevent absorption of iodine from water or food, resulting in ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1995.1057
更新日期：1995-05-01 00:00:00
abstract：:The effect of salmon calcitonin (0.25 MRC mU/g body wt) was investigated on the serum calcium and inorganic phosphate levels of the frog. Rana tigrina. The hormone evokes hypocalcemia (on Day 1 and Day 3) which is followed by a significant hypercalcemia on Day 10. Thereafter, the level of calcium decreases again on Da...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(89)90109-3
更新日期：1989-04-01 00:00:00
abstract：:To study the effects of glucocorticoids and IGF-I on the modulation of growth in the tilapia Oreochromis mossambicus, we employed an epiceratobranchial cartilage radioisotope incorporation assay, wherein radiolabeled sulfate and thymidine uptakes are measured in vitro to indicate proteoglycan synthesis and cell prolif...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.2000.7599
更新日期：2001-03-01 00:00:00
abstract：:Our previous study showed that docosahexaenoic acid (DHA) plays an important role in decreasing lipid accumulation by inducing apoptosis of the adipocytes in grass carp. However, the mechanism involved remains unclear. DHA has been reported as the natural ligand of PPARγ. The present study aimed to assess whether PPAR...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2018.05.020
更新日期：2018-09-15 00:00:00
abstract：:Chickens were used as a model to further analyze the efficacy and specificity of L-692,429, a novel nonpeptidyl mimic of growth hormone (GH)-releasing peptide-6 (GHRP-6), which is a specific GH-releasing secretagogue in mammals. Actions at the level of the pituitary and the hypothalamus were studied. Pituitaries isola...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1998.7102
更新日期：1998-08-01 00:00:00
abstract：:The zebrafish is a powerful genetic model organism. In recent years, zebrafish has been increasingly used to model human diseases. Due to a number of recent technological advancements, the genetic tool box is now also stocked with sophisticated transgenic and reverse genetic tools. Here, we focus on both commonly used...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2013.02.002
更新日期：2013-07-01 00:00:00
abstract：:The parathyroid glands of chickens were autotransplanted and the return of parathyroid function following transplantation was determined. Parathyroidectomy (PTX) resulted in a marked hypocalcemia (5.2 +/- 0.2 mg/dl) 4 hr following PTX. Plasma calcium (PCa) had declined to 4.3 +/- 0.2 mg/dl 24 hr after PTX. Parathyroid...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(89)90142-1
更新日期：1989-12-01 00:00:00
abstract：:Although 11-ketotestosterone (11-KT) has been found in blood of females of several diadromous fish species, the importance, abundance, and prevalence of this and related 11-oxygenated androgens in females have not been investigated. To address this issue and to determine whether the differences among androgen profiles...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/s0016-6480(02)00562-2
更新日期：2002-10-15 00:00:00
