Abstract:
:Insulin receptor downregulation in the isolated hepatocytes of lamprey (Lampetra fluviatilis) was studied at the ambient temperature for this species. Preincubation of hepatocytes with 10(-9)-10(-8) M unlabeled insulin decreased insulin binding capacity to 43, 37, and 34% at 4, 15, and 25 degrees, respectively. Preincubation of hepatocytes in the presence of 10(-10) M unlabeled insulin had no effect on the 125I-insulin binding. The maximal decrease in the 125I-insulin binding was reached after 10 min of preincubation and was then maintained at a constant level for 2 hr. Competitive binding assays demonstrated that preincubation with unlabeled insulin resulted in a 45% decline in the number of binding sites. In rat adipocytes and frog hepatocytes used for the comparison, preincubation with insulin caused a 65% decrease in cell-surface receptors, while intracellular (internalized receptors) increased proportionally. In contrast, in the lamprey hepatocytes both cell-surface and intracellular receptors decreased. We conclude that insulin receptors of the lamprey hepatocytes could be down-regulated at the ambient temperature for the species and at the physiological concentrations of insulin (10(-9)-10(-8) M).
journal_name
Gen Comp Endocrinoljournal_title
General and comparative endocrinologyauthors
Leibush BN,Lappova YLdoi
10.1006/gcen.1995.1126subject
Has Abstractpub_date
1995-10-01 00:00:00pages
10-7issue
1eissn
0016-6480issn
1095-6840pii
S0016-6480(85)71126-4journal_volume
100pub_type
杂志文章abstract::Follicular development and oocyte recruitment were studied in the ovaries of long-term (2 months) hypophysectomized frogs Rana cyanophlyctis during the postbreeding season (October/November). The effects of homoplastic pituitary pars distalis homogenate (PDH) (1 pituitary per frog), 40 IU pregnant mare serum gonadotro...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(85)90260-6
更新日期:1985-02-01 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::A protein with insulin-like effects was isolated from the hepatopancreas of the lobster Panulirus argus following a classic method for mammalian insulin purification from the pancreas. After acid-alcoholic extraction and ethanol-ether precipitation followed by molecular filtration chromatography, a protein with an app...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/s0016-6480(03)00014-5
更新日期:2003-05-01 00:00:00
abstract::The neurohypophyseal hormones of the hippopotamus (Hippopotamus amphibius) and collared peccary (Tayassu angulatus) were isolated by molecular sieving and preparative high-pressure liquid chromatography (HPLC). Oxytocin and arginine vasopressin have been identified by their amino acid compositions and their retention ...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(88)90277-8
更新日期:1988-09-01 00:00:00
abstract::Growth hormone (GH) and insulin-like growth factor-I (IGF-I) play major roles in the endocrine regulation of fish growth, but their interdependency and mode of action has not been well elucidated. The GH-IGF-I system is essential for normal vertebral growth in mouse, but this has not been studied in fish. To study the...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2004.12.005
更新日期:2005-05-15 00:00:00
abstract::The phenomenon of musth is a very stressful event, both behaviorally and physiologically. An ACTH stimulation test was conducted in four adult Asian bull elephants to investigate the possibility that the classical hypothalamic-pituitary-adrenal (HPA) axis is active during musth, resulting in an increase in adrenally p...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2007.01.029
更新日期:2007-05-01 00:00:00
abstract::Using antibodies to the amino-terminal region of human parathyroid hormone-related protein (PTHrP) we have demonstrated PTHrP immunoreactivity in pituitaries and plasma of the sea bream (Sparus aurata). Pituitary cells at two distinct locations contained immunodetectable PTHrP; an anterior group in the rostral pars di...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1993.1156
更新日期:1993-11-01 00:00:00
abstract::Potamopyrgus antipodarum is a promising test organism that is often used in ecotoxicology, both in laboratory and field exposures. As no data are available on the physiological variation range of its life-traits and the biomarkers it uses, we studied the variation of fecundity, steroid levels and energy reserves over ...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2011.03.011
更新日期:2011-06-01 00:00:00
abstract::In the genetic sex determination of vertebrates, the gonadal sex depends on the combination of sex chromosomes that a zygote possesses. Despite the discovery of the sex-determining gene (SRY/Sry) in mammals in 1990s, the sex-determining gene in non-mammalian vertebrates remained an enigma for over a decade. In most ma...
journal_title:General and comparative endocrinology
pub_type: 杂志文章,评审
doi:10.1016/j.ygcen.2015.10.004
更新日期:2016-12-01 00:00:00
abstract::Behavioral, biochemical, and electrophysiological studies suggest that the trihydroxylated progestin steroid, 4-pregnen-17,20beta,21-triol-3-one (20beta-S) stimulates oocyte maturation and pheromone release in the Eurasian ruffe, a freshwater percid fish. Behavioral observations found that female ruffe undergoing oocy...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2004.05.014
更新日期:2004-10-01 00:00:00
abstract::Free-living starlings (Sturnus vulgaris) were caught by mist netting. Blood samples were taken from them between 20 sec and 4 min after capture and assayed for corticosterone. Before 1 min corticosterone levels were constant (10.3 nmol litre-1) but after 1 min they increased rapidly (27.0 +/- 3.6 nmol litre-1 min-1). ...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(83)90085-0
更新日期:1983-08-01 00:00:00
abstract::Over the last decade, field endocrinologists have explored the efficacy of using plasma corticosterone concentrations of breeding seabirds as an indicator of food availability and predictor of breeding success. However, studies have been predominately confined to adults and the results have been inconsistent. We exami...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2008.01.010
更新日期:2008-04-01 00:00:00
abstract::Arginine vasotocin (AVT) and isotocin (IT) are fish hypothalamic nonapeptides involved in numerous social and reproductive behaviors. Vasotocinergic and isotocinergic fibers project to different brain areas where peptides act as neurotransmitters and/or neuromodulators. In this study, we measured whole brain levels of...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2014.04.039
更新日期:2014-08-01 00:00:00
abstract::A detailed study was made of sex differentiation in three anteroposteriorly distributed body regions of the long gonadal fold in young Pacific hagfish (Eptatretus stouti) from 12.4 to 45 cm in length. In general, the posterior region, adjacent to the cloaca, remained undifferentiated, and only in specimens more than 2...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(90)90315-d
更新日期:1990-02-01 00:00:00
abstract::This experiment was performed on two groups of male Japanese quail. One had been maintained in our laboratory as a closed colony (S-group), and the other had been obtained from a commercial source (R-group). Different responses of gonadal function were found between two groups following either testosterone treatment o...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(85)90390-9
更新日期:1985-09-01 00:00:00
abstract::High levels of the amino acid neurotransmitter glutamate were found in the goldfish hypothalamus and pituitary using high performance liquid chromatography with fluorometric detection. A specific polyclonal antibody to glutamate was generated in the rabbit for immunocytochemistry. Localization studies demonstrated tha...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1996.0103
更新日期:1996-08-01 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 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::Plasma progesterone concentrations were measured every 2 or 3 days in eastern quoll, Dasyurus viverrinus, during pregnancy (20.5 +/- 0.8 days, n = 6, mean +/- SEM) and the estrous cycle (37.5 +/- 0.7 days, n = 20, mean +/- SEM). The pattern was not apparently different between the two reproductive states. There was a ...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(89)90015-4
更新日期:1989-07-01 00:00:00
abstract::In vivo studies were carried out in adult chickens in an attempt to evaluate the effectiveness of somatostatin (SRIF) in regulating hormone secretion from the splenic pancreatic lobe after 99% of the pancreatic mass was surgically ablated. Sixteen days after either sham operation or 99% pancreatectomy, birds were infu...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(86)90166-8
更新日期:1986-08-01 00:00:00
abstract::In many mammal species, androgen levels in males are elevated during periods of mating activity, often to facilitate aggressive behavior between males over access to fertile females. However, this pattern might be less obvious in species with a rather low male-male aggression rate, or in those that are not strictly se...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2017.09.028
更新日期:2018-01-01 00:00:00
abstract::Insulin is an extensively studied peptide hormone in mammals. However, insulin is not restricted to vertebrates, but has also been identified in invertebrates, among whom several insect species. These insulin-like peptides (ILPs) show structural and-at least some-functional homology with mammalian insulin and act thro...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2007.05.001
更新日期:2007-08-01 00:00:00
abstract::The role of ovarian hormones in the expression of parental behavior and in the regulation of LH secretion was investigated in incubating commercial meat-type hens. After ovariectomy, incubating hens continued to incubate eggs normally and brooded day-old chicks given to replace eggs, in a manner similar to sham-ovarie...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1996.0013
更新日期:1996-01-01 00:00:00
abstract::The present study was designed to investigate potential effects of arachidonic acid (ARA) on the reproductive physiology of female Atlantic cod (Gadus morhua L.). Two-year old Atlantic cod of both sexes were equally distributed into eight sea cages after completion of their first spawning in May 2005. Four experimenta...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2017.05.020
更新日期:2017-09-01 00:00:00
abstract::The neuroendocrine system integrates genotype with external factors such as nutrition to regulate animal growth. To investigate the role of somatotropic axis in the interaction of genotype and nutrition, two series of experiments were conducted using broiler and layer chickens as a model. In the first experiment, both...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2003.11.009
更新日期:2004-03-01 00:00:00
abstract::We evaluated the effect of corticotropin-releasing hormone (CRH) on spatial distribution and downstream movement in an artificial stream in juvenile Chinook salmon (Oncorhynchus tshawytscha) during the period when the fish were able to tolerate seawater. An intracerebroventricular (ICV) injection of CRH (500 ng) to ha...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2004.02.004
更新日期:2004-05-15 00:00:00
abstract::This study was designed to examine the relationship among ovulation rate, inhibin alpha-subunit gene expression, and plasma immunoreactive inhibin levels between hens laying at a high ovulation rate and hens laying at a low ovulation rate. A porcine inhibin alpha-subunit cDNA was used to examine the expression of inhi...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1993.1103
更新日期:1993-07-01 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::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::Maintenance of cellular homeostasis influences ageing and it is determined by several factors, including efficient proteolysis of damaged proteins. The ubiquitin-proteasome system is the major protein degradation pathway in the cell. Specifically, the proteasome is responsible for clearance of abnormal, denatured or i...
journal_title:General and comparative endocrinology
pub_type: 杂志文章,评审
doi:10.1016/j.ygcen.2011.02.005
更新日期:2011-05-15 00:00:00