Abstract：
:The effects of calcium on steroidogenesis and cyclic AMP production in chicken granulosa cells were examined. For the expression of full steroidogenic effects by LH, forskolin, and 8-bromo cyclic AMP the presence of calcium in the incubation medium was essential, the optimal concentration being 1 mM. Moreover, calcium antagonists (verapamil, TMB-8) significantly suppressed steroidogenesis in response to all three agonists. The metabolism of 25-hydroxycholesterol and the conversion of pregnenolone to progesterone, however, were not affected by the lack of calcium or by coincubation with calcium antagonists. LH-stimulated cyclic AMP production was also suppressed in calcium-deficient medium and in the presence of the putative calcium channel blocker, verapamil. However, TMB-8 did not affect LH-induced cyclic AMP production. Moreover, neither forskolin- nor IBMX-induced cyclic AMP accumulation was significantly affected by lack of calcium or verapamil. These results are interpreted to indicate that the continuous presence of extracellular calcium is essential for hormonal regulation of steroidogenesis and is important for events both proximal and distal to cyclic AMP generation up to pregnenolone synthesis.
journal_name
Gen Comp Endocrinoljournal_title
General and comparative endocrinologyauthors
Asem EK,Hertelendy Fdoi
10.1016/0016-6480(86)90100-0subject
Has Abstractpub_date
1986-04-01 00:00:00pages
120-8issue
1eissn
0016-6480issn
1095-6840pii
0016-6480(86)90100-0journal_volume
62pub_type
杂志文章abstract：:The actions of mammalian insulin-like growth factors (IGF-I and IGF-II) and insulin on skeletal growth of the axolotl, Ambystoma mexicanum, were examined by monitoring the in vitro uptake of [35S]sulfate by cartilage. Both growth factors stimulated sulfate uptake significantly at a concentration of 13 nM. The increase...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1996.0145
更新日期：1996-10-01 00:00:00
abstract：:The activities of oxidative enzymes of hepatic mitochondria of Anabas testudineus increased following exogenous administration of hydrocortisone and corticosterone. The inhibitors of protein synthesis prevented the hormone-mediated increase of hepatic enzymes, suggesting that corticosteroids regulate the oxidative met...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(90)90017-g
更新日期：1990-05-01 00:00:00
abstract：:Recently, we demonstrated high serum leptin and 25(OH)D (calcidiol) in obese animals, with high C/EBPβ and PPARγ expression in adipose tissue. Since the role of vitamin D in adipogenesis remains controversial and hyperleptinemia is found in obesity, we asked if leptin could interfere in vitamin D action on adipocytes....
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2018.01.014
更新日期：2018-09-15 00:00:00
abstract：:Growth hormone (GH) regulates essential physiological functions in teleost fishes, including growth, metabolism, and osmoregulation. Recent studies have identified two clades of putative receptors for GH (GHR1 clade and GHR2 clade) in fishes, both of which are highly expressed in the liver. Moreover, the liver is an i...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2012.07.010
更新日期：2012-10-01 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：: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：:In mammals, leptin plays an important role in puberty and reproduction and leptin is regulated by sex steroids. Elevated leptin levels have been associated with sexual maturation in some teleosts such as Atlantic salmon. In the present study, primary cultures of Atlantic salmon hepatocytes were used to investigate the...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2015.01.015
更新日期：2015-09-15 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：:Under 25 degrees C and a long day photoperiod, about half of the fourth instar Psacothea hilaris larvae molt to the fifth instar on day 13 and pupate about 18 days later; the rest pupate without a further larval molt with a mean fourth instar period of 24 days. However, starvation of fourth instar larvae exceeding a t...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2005.05.006
更新日期：2005-11-01 00:00:00
abstract：:Previous reports have shown that adenosine in rat inhibits both spontaneous and ACTH-induced release of corticosteroids through activation of adenosine A1 receptors. In the present study, we have investigated the possible effect of adenosine in the secretion of corticosteroids in amphibians using a perfusion technique...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(92)90070-z
更新日期：1992-06-01 00:00:00
abstract：:Plasma levels of corticosterone and aldosterone were determined by radioimmunoassay in ducks consuming diets containing different concentrations of sodium and potassium. Compared with control diet birds, maintenance on a high-Na+ diet for 5 days caused a 2-fold increase in the basal plasma corticosterone concentration...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(85)90131-5
更新日期：1985-04-01 00:00:00
abstract：:Three distinct thyroid hormone receptor (TR) cDNAs (gTRalphaA, gTRalphaB and gTRbeta) were cloned and sequenced in orange-spotted grouper (Epinephelus coioides). The cDNA of gTRalphaA consisted of 1555-bp and encoded a putative protein of 416 amino acids, while the cDNA of gTRalphaB consisted of 1459-bp and encoded 39...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2008.08.015
更新日期：2008-11-01 00:00:00
abstract：:Wrasse species exhibit a definite daily rhythm in locomotor activity and bury themselves in the sand at the bottom of the ocean at night. It remains unclear how their behavior in locomotor activity is endogenously regulated. The aim of the present study was to clarify the involvement of melatonin and clock genes (Per1...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2012.01.007
更新日期：2012-05-15 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：:In this study, we compare the ontogenic patterns for thyroid hormones, growth hormone (GH), and insulin-like growth factor-I (IGF-I) in altricial European starlings and precocial Japanese quail and examine the effects of feed restriction on these species. The most marked difference in development between the altricial...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1996.0033
更新日期：1996-03-01 00:00:00
abstract：:In order to investigate the ontogeny of steroid secretions during the juvenile phase, sexual steroids were extracted and assayed after chromatographic separation in the gonads and plasma of male and female salamanders Salamandra salamandra L. at three characteristic postlarval stages. All specimens were collected in t...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(91)90127-r
更新日期：1991-01-01 00:00:00
abstract：:The conversion in vitro of cholesterol (Ch) to nonpolar metabolites and ecdysteroids was studied in Y-organs of the xanthid crab, Menippe mercenaria. In one set of experiments, Y-organs were prelabeled in vivo by injecting crabs with 100 microCi of [3H]Ch, and halved glands were then incubated for 24 and 48 hr in the ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(92)90255-i
更新日期：1992-11-01 00:00:00
abstract：:The avian neurohypophyseal hormone arginine vasotocin (AVT) is known to be involved in the regulation of adrenocorticotropin (ACTH) release by interacting with the VT2 receptor (VT2R), which is homologous to the mammalian vasopressin V1b receptor (V1bR). To study the role of glucocorticoid in the expression and regula...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2008.12.019
更新日期：2009-04-01 00:00:00
abstract：:Gonads are the main source of sex steroids, which have been implicated in the regulation of sexually differentiated behavior, such as reproductive and aggressive displays. In the Mozambique tilapia (Oreochromis mossambicus) territorial males have higher androgen levels than non-territorials, express reproductive behav...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2014.03.018
更新日期：2014-10-01 00:00:00
abstract：:Organophosphorus pesticides are known to disturb glucose homeostasis and increase incidence of metabolic disorders and diabetes via insulin resistance. The current study investigates the influence of malathion on insulin signaling pathways and the protective effects of N-acetylcysteine (NAC). Malathion (200 mg/kg) and...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2014.10.002
更新日期：2015-05-01 00:00:00
abstract：:Baleen whales are vulnerable to environmental impacts due to low fecundity, capital breeding strategies, and their reliance on a large amount of prey resources over large spatial scales. There has been growing interest in monitoring health and physiological stress in these species but, to date, few measures have been ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2020.113436
更新日期：2020-05-15 00:00:00
abstract：:Big dynorphin (prodynorphin 209-240), dynorphin A (prodynorphin 209-225), dynorphin B (prodynorphin 228-240), beta-endorphin (beta-lipotrophin 61-90), or Met-enkephalin, each infused into the third ventricle, were tested for their effect on PRL release in the anesthetized turkey hen. Laying hens that received big dyno...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1993.1121
更新日期：1993-08-01 00:00:00
abstract：:Dopamine (DA) has a pivotal role in avian prolactin (PRL) secretion, acting centrally through D(1) DA receptors to stimulate PRL secretion by operating through vasoactive intestinal peptide (VIP). DA also inhibits PRL secretion by activating D(2) DA receptors at the pituitary level. This study was designed to investig...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2008.08.002
更新日期：2008-10-01 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：: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
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：:The somatotropic axis, or growth hormone-insulin-like growth factor-1 (GH-IGF-1) axis, of fish is involved in numerous physiological process including regulation of ionic and osmotic balance, lipid, carbohydrate and protein metabolism, growth, reproduction, immune function and behavior. It is thought that GH plays a r...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2013.08.018
更新日期：2013-12-01 00:00:00
abstract：:The potential effects of growth hormone (GH), prolactin (Prl), and triiodothyronine (T3) on gill Na+,K+-ATPase activity and corticosteroid receptor (CR) concentration (Bmax) and dissociation constant (Kd) were examined in juvenile Atlantic salmon (Salmo salar). Compared to controls, fish injected with GH (ovine, 5.0 m...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1998.7172
更新日期：1998-11-01 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：:The Atlantic Bluefin Tuna (ABFT, Thunnus thynnus) is one of the most intensely exploited fisheries resources in the world. In spite of the years of studies on ABFT, basic aspects of its reproductive biology remain uncertain. To gain insight regarding the seasonal changes of the reproductive characteristics of the east...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2019.113216
更新日期：2019-10-01 00:00:00
