Abstract：
:In order to examine the role of thyroid hormones during salmonid development, techniques were developed for quantitative extraction of thyroxine from eggs, whole embryos, and alevins of chum salmon (Oncorhynchus keta) at various stages of development. Frozen eggs, embryos, alevins, or fry were homogenized in ice-cold methanol. The homogenate was centrifuged, and the supernatant was washed with a mixture of chloroform and 0.05% CaCl2. The aqueous layer was lyophilized, and the residue was redissolved in barbital buffer for thyroxine radioimmunoassay (RIA). Serial dilutions of the egg or tissue extracts gave inhibition slopes that were parallel to that of the thyroxine standard in the RIA. Immunoreactivity of the extracts coeluted with thyroxine standard in reverse-phase HPLC on an ODS column. Recovery of thyroxine from egg and tissue extracts was estimated from the recovery of 125I-labeled thyroxine added to the initial homogenates. Thyroxine content of eggs just after fertilization was 4-5 ng/egg, and this level was maintained until hatching. A decrease in thyroxine content was seen during yolk absorption. Total thyroxine increased to about 10 ng/fish, a level higher than that in the unfertilized egg, at the time of complete yolk absorption, and decreased within 10 days to a low level of 1 ng/fish. These findings are discussed in relation to the role of maternal thyroid hormones during early development and also to the onset of larval thyroid function.
journal_name
Gen Comp Endocrinoljournal_title
General and comparative endocrinologyauthors
Tagawa M,Hirano Tdoi
10.1016/0016-6480(87)90068-2subject
Has Abstractpub_date
1987-10-01 00:00:00pages
129-35issue
1eissn
0016-6480issn
1095-6840journal_volume
68pub_type
杂志文章abstract：:Female red-sided garter snakes (Thamnophis sirtalis parietalis) exhibit a complex array of behavioral patterns. Females may mate once, more than once, or not at all in the spring of the year, and a high percentage of females may mate in late summer before returning to winter hibernacula. The role of mating in the indu...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(86)90243-1
更新日期：1986-01-01 00:00:00
abstract：:A growing number of studies have examined transcriptional responses to sex steroids along the hypothalamic-pituitary-gonadal axis in teleost fishes. However, data are lacking on the molecular cascades that underlie progesterone signaling. The objective of this study was to characterize the transcriptional response in ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2013.06.008
更新日期：2013-10-01 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：:In the present study, four full-length cDNAs of somatostatin receptor (sstr) were cloned from the forebrain and pituitary of red-spotted grouper. The four full-length cDNAs were designated 2292, 1522, 1873 and 1789 bp and identified as sstr1, sstr2, sstr3, and sstr5 by BLAST analysis; the corresponding sizes of the op...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2019.01.007
更新日期：2019-04-01 00:00:00
abstract：:Urinary corticosterone metabolite responses to capture have recently been shown for the first time in amphibians, and in the present study urinary corticosterone metabolite responses to capture and to confinement in captivity were measured in adult cane toads (Rhinella marina) in Queensland, Australia. An adrenocortic...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2011.06.015
更新日期：2011-09-01 00:00:00
abstract：:The photoperiodic control of puberty in birds was studied using hybrid red-legged partridges (Alectoris graeca chukar). In the wild partridges first breed at about 10 months of age. Males and females were held from hatch on short (8L:16D) daylengths and then at 3, 4 1/2, 6, 7 1/2, 9, and 12 weeks of age groups were tr...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(88)90290-0
更新日期：1988-07-01 00:00:00
abstract：:Seasonal and daily variation in basal plasma concentrations of corticosterone and the effect of short-term confinement on plasma corticosterone concentration were examined in wild adult male and female tuatara (Sphenodon punctatus) on Stephens Island, New Zealand. Males and females sampled immediately upon capture at ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1997.7051
更新日期：1998-05-01 00:00:00
abstract：:In fish, luteinizing hormone (LH) stimulates processes leading to final oocyte maturation and ovulation in females, and spermiation in males. The hormone is a heterodimeric glycoprotein composed of two non-covalently associated subunits. In this study, we describe the expression of tilapia LH (tLH) as a biologically a...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2004.10.016
更新日期：2005-02-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(85)90075-9
更新日期：1985-12-01 00:00:00
abstract：:The role of stress in the decline of Steller sea lions has become of interest in the identification of factors leading to their drastic decline and subsequent failure to recover. Serum cortisol was validated as a potential indicator of stress in three sub-populations inhabiting the majority of the Steller sea lions ra...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2009.06.006
更新日期：2010-01-01 00:00:00
abstract：:The skin is the largest organ in the body and is a barrier between the internal and external environment. The present study evaluates how PTU, a goitrogen, that is used to treat hyperthyroidism affects the structure and electrical properties of the frog (Xenopus laevis) skin. The results are considered in the context ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2011.09.007
更新日期：2011-12-01 00:00:00
abstract：:Plasma levels of testosterone and corticosterone were measured in free-living male bush warblers captured on their breeding ground at different times of the breeding season. Their territoriality was also estimated from their singing response to song playbacks. The pattern of change detected in the levels of plasma tes...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1999.7381
更新日期：1999-12-01 00:00:00
abstract：:Cortisol is an important seawater (SW) osmoregulatory hormone in the Mozambique tilapia (Oreochromis mossambicus), a highly euryhaline cichlid able to live in environments ranging from fresh water (FW) to salinities well in excess of full-strength seawater. Previous studies indicate that cortisol may promote SW adapta...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/s0016-6480(03)00053-4
更新日期：2003-06-01 00:00:00
abstract：:We studied the in vitro effects of JH III and ecdysterone on RNA synthesis and secretory activities of the left colleterial gland (LCG) in mature females of Periplaneta americana during the reproductive cycle. We found that RNA synthesis is a cyclic and highly dynamic process. The major increases in poly(A)- RNA synth...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(88)90301-2
更新日期：1988-07-01 00:00:00
abstract：:Relaxin 3 (RLN3) is a newly-discovered member of the insulin superfamily. We isolated three RLN3-like cDNAs from the brain of the Japanese eel (Anguilla japonica). The deduced amino acid sequences of the RLN3-like cDNAs contained the two-chain structure common to relaxin including a RXXXRXXI/V motif in the B-chain. Ph...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2011.04.013
更新日期：2011-07-01 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：:The brain of many teleost fish species, including the goldfish Carassius auratus, expresses exceptionally high levels of cytochrome P450 aromatase (estrogen synthetase). To begin investigating the molecular and cellular targets of estrogen action in goldfish brain, a polymerase chain reaction (PCR) cloning strategy wa...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1998.7217
更新日期：1999-03-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2004.09.010
更新日期：2005-01-01 00:00:00
abstract：:The effect of bursa of Fabricius on the endocrine function of the chick testis was studied using an isolated testis cell preparation. Testosterone secretion, both basal and under hCG stimulation, was measured in the incubation medium. The bursal extract inhibited the response of the testis cells to hCG detected as a r...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(85)90208-4
更新日期：1985-01-01 00:00:00
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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：:In captivity, the adrenocortical stress response can be permanently altered by events that occur during early life. Free-living animals have rarely been examined in this regard. To examine whether early-life events impact the hypothalamo-pituitary-adrenal (HPA) axis in the natural setting, we evaluated the stress resp...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2011.08.022
更新日期：2011-11-01 00:00:00
abstract：:The Remipedia is a small, recently described crustacean class that inhabits submerged marine/anchialine cave systems. Phylogenetic and morphological investigations support a sister group relationship between these animals and the hexapods. The recent deposition of numerous (>100,000) transcriptome shotgun assembly seq...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2014.01.017
更新日期：2014-05-15 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：: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：:In the teleost brain, radial glial cells (RGCs) are the main macroglia and are stem-like progenitors that express key steroidogenic enzymes, including the estrogen-synthesizing enzyme, aromatase B (cyp19a1b). As a result, RGCs are integral to neurogenesis and neurosteroidogenesis, however little is known about the reg...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2017.04.014
更新日期：2018-02-01 00:00:00
abstract：:A reliable and rapid technique for the measurement of estradiol-17 beta, testosterone, progesterone, 17 alpha-hydroxyprogesterone, 17 alpha,20 beta-dihydroxy-4-pregnen-3-one, and cortisol by reverse-phase high-performance liquid chromatography and radioimmunoassay in single female goldfish serum samples of 50 microlit...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(89)90135-4
更新日期：1989-12-01 00:00:00
abstract：:Genetic sex determination leads to gonadal differentiation and ultimately the differences between the sexes in steroid hormone secretion. Gonadal steroidogenesis is critical for the development of a sexually dimorphic phenotype and adult reproductive function. Control of gonadal development and steroidogenesis is unde...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/s0016-6480(02)00019-9
更新日期：2002-06-01 00:00:00
abstract：:Serum cortisol levels were measured in a total of 73 tammar wallabies maintained in a captive population at Macquarie University, NSW, Australia. Previous studies of corticosteroids in marsupials have generally involved low sample numbers, a diverse array of analytical techniques, and a variety of sampling conditions....
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/s0016-6480(03)00185-0
更新日期：2003-10-01 00:00:00
abstract：:The pattern and kinetics of degradation of native salmon gonadotropin-releasing hormone (sGnRH) and mammalian leuteinizing hormone-releasing hormone (LHRH) by pituitary bound enzymes were studied in the gilthead seabream, Sparus aurata. sGnRH and LHRH were incubated for different periods of time with membrane or cytos...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(90)90115-3
更新日期：1990-08-01 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
