Abstract：
:The chromatographic profile of ecdysteroids (Ecds) from the midgut gland (MG) of juvenile female lobsters, Homarus americanus, was examined using high-performance liquid chromatography (HPLC) and radioimmunoassay (RIA) over four stages of the molt cycle. Upon initial examination, highly polar Ecd conjugates appeared to be the principal metabolites found in all molt stages. HPLC fractions containing apolar Ecds initially exhibited low RIA activity. Upon hydrolysis with a Helix pomatia enzyme preparation and reanalysis, significant amounts of other Ecds were released. Amounts of apolar Ecd conjugates were estimated, at their highest levels, to be at least 50% of the total Ecds in MGs of molt stage D3 lobsters. Only the MG formed significant amounts of apolar Ecds upon in vitro culture with [3H]ecdysone ([3H]E). Epidermis and antennal gland significantly increased their rates of [3H]E metabolism in vitro between molt stages C4 and D1. This result further supports the idea that regulation of ecdysteroid metabolism, at least in selected tissues, may be important in the molt cycle regulation of hormone titers. Using gel filtration column chromatography and sucrose density gradient centrifugation analyses, evidence was found for association of apolar Ecds with a protein(s) from MG cytosol. The protein was estimated to have a molecular weight of 180,000-200,000 and specifically bound apolar Ecds.
journal_name
Gen Comp Endocrinoljournal_title
General and comparative endocrinologyauthors
Snyder MJ,Chang ESdoi
10.1016/0016-6480(92)90013-akeywords:
subject
Has Abstractpub_date
1992-02-01 00:00:00pages
286-96issue
2eissn
0016-6480issn
1095-6840pii
0016-6480(92)90013-Ajournal_volume
85pub_type
杂志文章abstract：:The aim of this work was to study, in the Cebus apella monkey, the developmental changes in the microanatomy of the utero-ovarian ligament (UOL) and whether their vascular and neural elements might be involved in the transfer of signals between the ovaries and uterus. Sections including uterus, UOL, and ovary obtained...
journal_title：General and comparative endocrinology
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pub_type： 杂志文章
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1994.1143
更新日期：1994-09-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2008.07.018
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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
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.2000.7571
更新日期：2000-12-01 00:00:00
abstract：:The purpose of this study was to investigate the physiological maturation-inducing steroid (MIS) in the marine protandrous yellowfin porgy (Acanthopagrus latus). Female fish were injected with 2 doses of LHRH analog (10 and 40 μg per kg). Ovarian tissue was obtained at 6 h intervals for in vitro analysis of oocyte mat...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2012.01.010
更新日期：2012-04-01 00:00:00
abstract：:Uptake of L-thyroxine (T4) by isolated trout hepatocytes was characterized after 1-min incubation of cells in a Hanks' balanced salts medium containing glucose and [125I]T4. Centrifugation through silicone oil and glycine buffer (pH 10.5) was used to separate cells from the medium and minimize extracellular binding of...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1993.1057
更新日期：1993-04-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(91)90145-v
更新日期：1991-09-01 00:00:00
abstract：:More and more evidence indicates that the insulin-like androgenic gland hormone (IAG) plays an important role in male sexual differentiation in crustaceans. In the present study, two IAG isoforms (Fc-IAG1 and Fc-IAG2) were identified from the penaeid shrimp Fenneropenaeus chinensis. Sequence analysis of IAG gene (Fc-I...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2012.04.010
更新日期：2012-06-01 00:00:00
abstract：:Laboratory populations of the prairie deermouse (Peromyscus maniculatus) reach a growth asymptote due primarily to the failure of more than 90% of the young born into the population to mature sexually. This inhibition is reversible; when young are removed from the inhibiting influence of the population more than 75% w...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/s0016-6480(02)00528-2
更新日期：2002-11-01 00:00:00
abstract：:The possible involvement of calcium in the regulation of steroidogenesis in the goldfish was investigated using preovulatory ovarian follicles incubated in vitro. Incubation of follicles in media deficient in calcium impaired testosterone production in response to human chorionic gonadotropin (hCG) in both the presenc...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(91)90011-t
更新日期：1991-02-01 00:00:00
abstract：:Plasma concentrations and stored levels of the neuroendocrine peptides arginine vasotocin (AVT) and urotensin II (UII) were measured in the euryhaline flounder (Platichthys flesus) following the acute hypo-osmotic challenge of direct seawater (SW) to fresh water (FW) transfer. Hormone measures, plasma osmolality, and ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.2001.7736
更新日期：2002-01-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1999.7363
更新日期：1999-11-01 00:00:00
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journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2013.10.004
更新日期：2014-01-01 00:00:00
abstract：:Factors potentially regulating hepatic growth hormone (GH) receptors in coho salmon (Oncorhynchus kisutch) have been investigated. From December to June of the first year, relative changes in hepatic 125I-sGH binding and 35SO4 incorporation by ceratobranchial cartilage were similar. Stunted salmon, which in seawater h...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(92)90256-j
更新日期：1992-11-01 00:00:00
abstract：:Calcitonin gene-related peptide (CGRP) was found using radioimmunoassay in the brain and spinal cord of the bullfrog, Rana catesbeiana. The brain extracts were found to contain 241.7 +/- 68.1 pg/mg tissue, and the spinal cord contained 1753.0 +/- 96.8 pg/mg tissue. An intense immunocytochemical reaction was observed i...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(88)90187-6
更新日期：1988-10-01 00:00:00
abstract：:The androgen concentration in birds' eggs varies with laying order, breeding conditions, and mate attractiveness. In passerine birds, mate attractiveness depends upon song quality. The aim of our study was to evaluate the effect of one criterion used by females to assess male song quality that is to say the presence o...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2004.05.010
更新日期：2004-09-01 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)90047-p
更新日期：1990-04-01 00:00:00
abstract：:Reverse-phase HPLC employing five different solvent systems was used to determine the 125I-labeled products formed in rainbow trout by in vitro incubation at 12 degrees of the hepatic microsome fraction with L-thyroxine (T4) labeled with 125I in the outer phenyl ring. Trout were starved for 2 weeks or fed a 2% ration....
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(92)90081-t
更新日期：1992-03-01 00:00:00
abstract：:Primary cultured gill epithelia from goldfish and rainbow trout were used to investigate a role for cortisol in the regulation of paracellular permeability and tight junction (TJ) protein transcript abundance in representative stenohaline versus euryhaline freshwater (FW) fish gills. Glucocorticoid and mineralocortico...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2011.04.023
更新日期：2011-07-01 00:00:00
abstract：:In altricial songbirds, food restriction in early development has adverse effects on various physiological systems. When conditions improve birds can accelerate growth, but this compensatory strategy is associated with long-term adverse consequences. One system affected by altered growth rates is the hypothalamic-pitu...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2015.08.001
更新日期：2015-10-01 00:00:00
abstract：:Intersex is defined as the simultaneous presence of male and female gonadal tissue in a gonochoristic (fixed-sex) species. The intersex condition has been documented in both wild and laboratory animals, including fish, amphibians, and reptiles. In aquatic animals, intersex is often viewed as a signature effect of expo...
journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
doi：10.1016/j.ygcen.2013.04.005
更新日期：2013-10-01 00:00:00
abstract：:We studied the hepatic in vitro deconjugation and deiodination of glucuronide (G) and sulfate (S) conjugates of the thyroid hormones (TH) thyroxine (T(4)), 3,5,3'-triiodothyronine (T(3)), and 3,3', 5'-triiodothyronine (rT(3)) in trout. These conversions have not been studied in nonmammals. Deconjugation of T(4)G, T(3)...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1999.7326
更新日期：1999-09-01 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：: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：:In fish there are few data on the gonadotropin-releasing hormone (Gn-RH) neurosecretory activity, which could explain long- and short-term variations of the gonadotropin secretion. There is no biological species specificity between mammal and fish Gn-RH; although there is a structural difference, they are, on the cont...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(86)90255-8
更新日期：1986-01-01 00:00:00
abstract：:We analyzed the participation of sympathetic ovarian innervation in the prepubertal female guinea pig on regulation of compensatory ovarian hypertrophy (COH) and compensatory ovulation at puberty. The COH of the left ovary was significantly higher that of the right one (left ovary: 41.5+/-5.2 vs. 27.5+/-5.6%, p<0.05, ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/s0016-6480(02)00061-8
更新日期：2002-07-01 00:00:00
abstract：:Plasma aldosterone levels of Bufo japonicus formosus captured in their natural environment were determined each month throughout 1 year by radioimmunoassay. Low values were recorded in winter and spring, and the maximum occurred in July or August. High summer levels of aldosterone and increases in live weight were cor...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(84)90237-5
更新日期：1984-01-01 00:00:00
abstract：:The insulin/PI3K/Akt signaling pathway is strongly involved in the differentiation of C2C12 cells, as has been demonstrated by the addition of IGFs and insulin to culture media. In this study, we have characterized the role of insulin in chick myoblast proliferation and differentiation in vitro and in vivo, and have r...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2011.11.043
更新日期：2012-02-01 00:00:00
