Abstract：
:Thyroidectomy of starlings (Sturnus vulgaris) prevents the decrease in hypothalamic gonadotrophin-releasing hormone (GnRH) which normally occurs at the onset of photorefractoriness. To extend this observation to another species, changes in testicular mass, bill colour, moult, and hypothalamic GnRH content were monitored in photostimulated and nonphotostimulated intact and thyroidectomized house sparrows (Passer domesticus). Photostimulated intact birds rapidly increased testicular mass and GnRH. Later, testicular mass and GnRH decreased, and birds moulted, as they became photorefractory. Nonphotostimulated intact birds showed an increase in testicular mass and GnRH. Neither photostimulated nor nonphotostimulated thyroidectomized birds showed a marked increase in testicular mass, but both showed an increase in GnRH. Photostimulated thyroidectomized birds showed no subsequent decrease in GnRH and they did not moult. It is suggested that in this species, thyroidectomy inhibits the release of GnRH as well as preventing the downregulation of GnRH synthesis normally associated with the development of photorefractoriness.
journal_name
Gen Comp Endocrinoljournal_title
General and comparative endocrinologyauthors
Dawson Adoi
10.1006/gcen.1998.7065subject
Has Abstractpub_date
1998-05-01 00:00:00pages
196-200issue
2eissn
0016-6480issn
1095-6840pii
S0016-6480(98)97065-4journal_volume
110pub_type
杂志文章abstract：:Studies with 6-n-propyl-2-thiouracil (PTU) in laboratory rodents have shown that transient neonatal hypothyroidism leads to increased Sertoli cell (SC) number, testis size and sperm production. However, scarce and inconclusive data are available for farm animals. In the present study, Piau pigs received PTU in a gel c...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2020.113593
更新日期：2020-12-01 00:00:00
abstract：:Faecal glucocorticoid metabolite (fGCM) concentrations have been used to evaluate adrenal activity in a variety of species; including as an indicator of the physiological response to social stress. However, across studies, the relationships between dominance rank, social behaviours and adrenal responses can be inconsi...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2013.02.023
更新日期：2013-06-01 00:00:00
abstract：:Effects of fasting on the growth hormone (GH)--growth hormone receptor (GHR)-insulin-like growth factor-I (IGF-I) axis were characterized in seawater-acclimated tilapia (Oreochromis mossambicus). Fasting for 4 weeks resulted in significant reductions in body weight and specific growth rate. Plasma GH and pituitary GH ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2006.04.007
更新日期：2006-09-15 00:00:00
abstract：:Although there is general agreement that thyroid hormone is an important hormonal regulator of testis physiology during development period, its role in the post-pubertal and adult testes is still controversial. Furthermore, most experimental studies to date have focused on thyroid hormone effects on the developing tes...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2011.08.012
更新日期：2011-11-01 00:00:00
abstract：:To examine the production of steroids with potential oocyte maturation-inducing or pheromonal activity in the goldfish (Carassius auratus) we have incubated mature ovaries of this species with 17-[3H]hydroxyprogesterone. The metabolites in the unconjugated, glucuronide, and sulfate fractions were identified by chromat...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(92)90044-k
更新日期：1992-09-01 00:00:00
abstract：:Ovarian follicles isolated from rainbow trout during early exogenous vitellogenesis were used to study the in vitro effects of thyroid hormones on salmon gonadotropin (GtH)-induced estradiol-17 beta (E2) secretion. Triiodothyronine (T3) alone did not alter E2 secretion but T3 in the presence of GtH (0.5 micrograms/ml)...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(88)90055-x
更新日期：1988-01-01 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：:Appetite and reproduction are closely related functions that are both regulated by brain hormones. Appetite stimulators include orexin and neuropeptide Y (NPY), and reproductive hormones include gonadotropin-releasing hormone (GnRH), gonadotropin-inhibitory hormone (GnIH), kisspeptin, and neurokinin B (NKB). GnRH stim...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2019.06.011
更新日期：2019-10-01 00:00:00
abstract：:In teleosts, sex is plastic and is influenced by environmental factors. Elevated temperatures have masculinizing effects on the phenotypic sex of certain sensitive species. In this study, we reared genetic XX Japanese flounder at a high temperature (27.5 ± 0.5 °C) and obtained a population of sex-reversal XX males (ma...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2018.12.012
更新日期：2019-04-01 00:00:00
abstract：:The messenger RNA expression for the inhibin/activin subunits in the granulosa layer of avian follicles of different developmental stages has previously been reported. In the present study, we examined the pattern of secretion of these protein subunits from cultured granulosa cells (GC) of avian follicles of defined m...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2005.01.006
更新日期：2005-05-01 00:00:00
abstract：:Determination of serum progesterone concentrations over a period of 2 years in female camels during various reproductive stages (estrus, pregnant, nonpregnant, and lactating) suggests that the progesterone levels exceeding 1 ng/ml are reached only if mating is fertile. A cycling camel does not have a luteal phase and ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(84)90248-x
更新日期：1984-02-01 00:00:00
abstract：:Gonadotropin-releasing hormone (GnRH) plays a central role in vertebrate reproduction. The evolutionary origin of this neuropeptide and its receptor is not obvious, but the advent of genomics makes it possible to examine the roots of GnRH and delve deeper into its ancestral relationships. New peptide sequences identif...
journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
doi：10.1016/j.ygcen.2010.12.014
更新日期：2011-03-01 00:00:00
abstract：:A highly specific and homologous radioimmunoassay (RIA) for the measurement of prolactin (PRL) in the plasma and the pituitary of the eel was developed using a rabbit antiserum to eel PRL. PRL was purified from the pituitary of Japanese eel (Anguilla japonica). Pituitary extracts and plasma from the Japanese and Europ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(91)90167-5
更新日期：1991-03-01 00:00:00
abstract：:Thyroid-dependent stomach development occurs between approximately 35 and 50 days post-hatch (dph) in laboratory-reared summer flounder larvae. The process can be blocked by thiourea (TU), and TU effects are reversed by exogenous thyroxine (T4). To establish whether a window of sensitivity exists for T4-dependent gast...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/s0016-6480(03)00262-4
更新日期：2003-12-01 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：:The aim of our study was to confirm the role of tidal pattern on the coordination of oocyte maturation and spawning in common snook Centropomus undecimalis. To do so, we studied oocyte maturation during the spawning season in relation to the tidal pattern in both males and females by means of histology and hormonal pr...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2015.08.007
更新日期：2015-12-01 00:00:00
abstract：:In fish, melatonin is reported to be produced mainly in the pineal organ, but there is also evidence for the presence of melatonin in a number of extrapineal sites where it could act as an intracellular mediator or paracrine signal. The present study use the reverse transcription-polymerase chain reaction (RT-PCR) to ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2006.12.008
更新日期：2007-06-01 00:00:00
abstract：:The larval ring gland and adult corpus allatum (CA) of Drosophila melanogaster produce at least three sesquiterpenoid products: methyl farnesoate (MF), juvenile hormone III (JHIII), and JHIII bisepoxide (JHB(3)). Our understanding of neuropeptide regulation of sesquiterpenoid biosynthesis in D. melanogaster has been h...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2011.12.039
更新日期：2012-05-01 00:00:00
abstract：:This study examines the regulation of thyroid activity in adult rough-skinned newts, Taricha granulosa. Aquatic, breeding-condition newts were hypophysectomized and were injected for 23 days with the mammalian adenohypophysial hormones: ACTH, PRL, and GH. During a fourth week of treatment, these newts also received TS...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(85)90385-5
更新日期：1985-08-01 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：:Histochemical assays, hormonal quantitation, and steroid biosynthetic studies were carried out with adrenal glands obtained from four stranded whales of two different species (Kogia breviceps and Mesoplodon europaeus), and selected comparisons were made with the results of similar studies of adrenals from terrestrial ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(87)90041-4
更新日期：1987-11-01 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：:In a series of experiments, the effect of cortisol on the ability of rainbow trout (Salmo gairdneri) ovarian follicles to secrete sex steroids in vitro was investigated. The basal rate of secretion of sex steroids (oestradiol and testosterone) was suppressed in a dose-dependent manner by the addition of cortisol to th...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(90)90230-j
更新日期：1990-03-01 00:00:00
abstract：:The effects of prolonged nutrient restriction (fasting) and subsequent restoration (re-feeding) on the growth hormone (GH)/insulin-like growth factor (IGF) axis were investigated in the tilapia (Oreochromis mossambicus). Mean weight and specific growth rate declined within 1 week in fasted fish, and remained lower tha...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2009.11.012
更新日期：2010-05-01 00:00:00
abstract：:In 1974, a lack of 5α-dihydrotestosterone (5α-DHT), the most potent androgen across species except for fish, was shown to be the origin of a type of pseudohermaphrodism in which boys have female-like external genitalia. This human intersex condition is linked to a mutation in the steroid-5α-reductase type 2 (SRD5α2) g...
journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
doi：10.1016/j.ygcen.2020.113400
更新日期：2020-05-01 00:00:00
abstract：:Chronic confinement for 1 month caused a significant elevation of plasma cortisol but suppressed the levels of plasma testosterone and 11-ketotestosterone in sexually mature male brown trout. An acute handling stress for 1 hr elevated blood cortisol and ACTH levels and also suppressed circulating androgens. This andro...
journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
doi：10.1016/0016-6480(87)90036-0
更新日期：1987-11-01 00:00:00
abstract：:Sex pheromones rapidly affect endocrine physiology and behaviour, but little is known about their effects on gene expression in the neural tissues that mediate olfactory processing. In this study, we exposed male goldfish for 6h to waterborne 17,20βP (4.3 nM) and PGF2α (3 nM), the main pre-ovulatory and post-ovulatory...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2013.06.015
更新日期：2013-10-01 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：:A mammalian isolated adrenal cell system was validated as a bioassay for goldfish ACTH; the log dose-response curve for the goldfish hormone is parallel to that for synthetic mammalian ACTH1-24, and the two ACTHs induce the same maximum rate of corticosterone production. Using this assay, it was observed that (1) ther...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(83)90010-2
更新日期：1983-01-01 00:00:00
abstract：:Classical biotin deficiency in young chickens is characterized by a reduction in the activity of liver biotin-dependent enzymes which thus impairs gluconeogenesis during periods of food withdrawal. Because the normal bird maintains an elevated fasting blood glucose level, the ability of the classically biotin-deficien...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(87)90232-2
更新日期：1987-01-01 00:00:00
