Abstract:
:The asymmetrical endostyle of Branchiostoma larvae contains two different zones of mucus-producing cells which metamorphose to the paired zones 2 and 4 respectively in the endostyle of the adult. In both the larva and the adult these zones are parts of the food-trapping mechanism. An endostyle zone, which has a position corresponding to that of the paired iodinating zones in the endostyle of the adult, binds iodine selectively. The ultrastructure and labeling pattern indicate that the labeled cells in the larval endostyle belong to functionally different types. In one region of the iodinating zone iodine is mainly bound extracellularly at the apical cell surface. Also in the second region grains are located at the apical cell surface as well as over the cytoplasm and extracellularly at the basal plasma membrane. It is possible that iodination takes place in the lumen close to cells in the first region and that the labeled product is taken up and eventually released by cells of the second region. Our observations show that this primitive endostyle already has iodinating capacity and may synthesize and release thyroid hormones.
journal_name
Gen Comp Endocrinoljournal_title
General and comparative endocrinologyauthors
Fredriksson G,Ericson LE,Olsson Rdoi
10.1016/0016-6480(84)90028-5subject
Has Abstractpub_date
1984-11-01 00:00:00pages
177-84issue
2eissn
0016-6480issn
1095-6840pii
0016-6480(84)90028-5journal_volume
56pub_type
杂志文章abstract::An investigation into vitamin D-like molecules has been performed on whole extracts of the terrestrial amphipod Orchestia cavimana, using a sensitive nonequilibrium assay employing 1,25-(OH)2 D receptor from calf thymus. Relatively large amounts of these secosteroid-like molecules were observed and they varied in conc...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(91)90070-m
更新日期:1991-10-01 00:00:00
abstract::The hypothesis that vasoactive intestinal peptide (VIP) functions as a hypothalamic prolactin (PRL)-releasing peptide in the turkey was tested by determining the effects of hypothalamic VIP immunoneutralization and pituitary VIP receptor blockade on hypothalamic extract (HE)-induced PRL secretion from dispersed anteri...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(90)90048-q
更新日期:1990-04-01 00:00:00
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::Several lines of evidence suggest reproduction in the ranid frogs is potently regulated by the gonadal steroids, in particular 5alpha-dihydrotestosterone (DHT) and 17beta-estradiol (E(2)), and a non-gonadal steroid, the stress hormone corticosterone (Cort). Little is known about how these steroid hormones act upon the...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2003.07.001
更新日期:2003-12-01 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::Progesterone, 4-androstenedione, testosterone, dihydrotestosterone, 5 alpha-androstane-3 alpha,17 beta-diol (3 alpha-diol), 5 alpha-androstane-3 beta, 17 beta-diol (3 beta-diol), estrone, and estradiol levels were determined by radioimmunoassay in the different lobules of the testis of Salamandra salamandra throughout...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(85)90337-5
更新日期:1985-05-01 00:00:00
abstract::Fluctuations in plasma androgen (testosterone and 5 alpha-dihydrotestosterone), corticosterone (B), and luteinizing hormone (LH) of male bullfrogs in central California were measured during the spring mating season. Androgen and LH levels generally increased in the population prior to the initiation of chorusing and e...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(85)90343-0
更新日期:1985-05-01 00:00:00
abstract::Fish egg yolk is largely derived from vitellogenins, which are synthesized in the liver, taken up from the maternal circulation by growing oocytes via receptor-mediated endocytosis and enzymatically processed into yolk proteins that are stored in the ooplasm. Lipid droplets are another major component of fish egg yolk...
journal_title:General and comparative endocrinology
pub_type: 杂志文章,评审
doi:10.1016/j.ygcen.2015.01.025
更新日期:2015-09-15 00:00:00
abstract::The oocytes of the freshwater catfish Heteropneustes fossilis hydrate during hormone-induced meiotic maturation. To investigate if this process may be mediated by aquaporins (AQPs), as it occurs in marine fish producing highly hydrated eggs, the cloning of ovarian AQPs in catfish was carried out. Using degenerate prim...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2010.10.002
更新日期:2011-01-01 00:00:00
abstract::Human pro-IGF-I Eb-peptide (hEb) and rainbow trout pro-IGF-I Ea-4-peptide (rtEa-4) have recently been shown to share unique biological activities [Gen. Comp. Endocrinol. 126 (2002) 342; Cell. Exp. Cell. Res. 280 (2002) 75]. To further understand the action mechanism of these proteins, we studied the binding properties...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/s0016-6480(03)00089-3
更新日期:2003-06-15 00:00:00
abstract::Development patterns in birds range from precocial species, which hatch chicks largely capable of independent existence, to altricial species, chicks of which are highly dependent on their parents for extended periods. Previous work indicates precocial chicks have a robust corticosterone response from hatching whereas...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2008.02.007
更新日期:2008-05-15 00:00:00
abstract::Fishes have evolved physiological mechanisms to exhibit stress response, where hormonal signals interact with an array of ion transporters and regulate homeostasis. As major ion transport regulators in fish, cortisol and thyroid hormones have been shown to interact and fine-tune the stress response. Likewise, in fishe...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2016.11.009
更新日期:2017-09-15 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::In this study, we cloned a full-length cDNA encoding vitellogenin (Vg) in the Fujian oyster Crassostrea angulata. The complete Vg cDNA consists of 5160 nucleotides with a long open reading frame encoding 1641 amino acid residues. The deduced amino acid sequence shared high similarity with the Vgs of other mollusc, fis...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2014.03.034
更新日期:2014-06-01 00:00:00
abstract::Thyroid hormones (TH) are key regulators of metabolism and development, yet our understanding of the variability in serum TH concentrations in free-ranging marine mammals is limited. Thus, we examined the interrelationships between TH and age, sex, reproductive status, geographic location, and ocean temperatures in wi...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2011.08.021
更新日期:2011-11-01 00:00:00
abstract::To examine the physiological role of calcitonin (CT) in calcium homeostasis of teleosts, we compared calcium and CT levels in freshwater eels fed a high calcium-consomme solution (Ca2+: 1.25 M; 1 ml/100 g body wt) into the stomach (Experiment I), and in freshwater eels transferred from freshwater to seawater (Experime...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1999.7261
更新日期:1999-06-01 00:00:00
abstract::Lampreys diverged from the jawed vertebrate lineage approximately 500million years ago. Lampreys undergo sex differentiation much later than most other vertebrates, and ovarian differentiation occurs several years before testicular differentiation. The genetic basis of lamprey sex differentiation is of particular inte...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2014.08.019
更新日期:2014-11-01 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::Melatonin and arylalkylamine N-acetyltransferase (AANAT), the rate-limiting enzyme in melatonin synthesis, have taken on special importance in vertebrate circadian biology. Recent identification of genes encoding two AANAT (AANAT(1) and AANAT(2)) and two subtypes of melatonin receptor (Mel-R; Mel(1a) and Mel(1b)) in s...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2004.01.004
更新日期:2004-05-01 00:00:00
abstract::In mammals, a well-documented inverse relationship exists between oral salt intake and plasma renin activity (PRA). We carried out this study to determine if a similar relationship exists in the freshwater turtle Pseudemys scripta. Three groups of turtles (N = 8 for each group) were fed different amounts of salt disso...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(89)90138-x
更新日期:1989-12-01 00:00:00
abstract::Gonadotropin-releasing hormone (GnRH) was detected in the brains of passerine birds, a recently evolved and diverse avian group. The molecular forms of GnRH in two species of birds under breeding conditions were deduced using methods of HPLC and immunology. The brain extracts of song sparrows (Melospiza melodia) conta...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(88)90024-x
更新日期:1988-03-01 00:00:00
abstract::The distribution and identity of the various endocrine cell types were examined in the pancreas, stomach, and anterior intestine of the phylogenetically ancient actinopterygian, the gar (Lepisosteus osseus L.), using immunohistochemistry. Antisera used were directed against several insulins (INSs) and somatostatins (S...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1996.6842
更新日期:1997-04-01 00:00:00
abstract::Daily variations in circulating melatonin concentrations have been measured at monthly intervals from April to December 1986 in an Antarctic bird, the emperor penguin, Aptenodytes forsteri, maintained under natural conditions. Both duration of the elevated nighttime melatonin levels and amplitude of the day-night rhyt...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(91)90048-b
更新日期:1991-11-01 00:00:00
abstract::Pangolins are 'keystone species' driven towards extinction due to a lack of profound awareness and illegal trade. The drivers urge for immediate development in the understanding of demographics and reproductive dynamics of this species. In this study, we developed and validated a quantitative method to measure pangoli...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2020.113607
更新日期:2020-12-01 00:00:00
abstract::We isolated and cloned full-length cDNAs of transthyretin (TTR) from 2 genera of lamprey, Petromyzon marinus and Lampetra appendix. These sequences represent the first report of TTR sequences in vertebrates basal to teleost fishes. The deduced amino acid sequence of lamprey TTR cDNAs showed 36-47% identity with those ...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2006.11.017
更新日期:2007-03-01 00:00:00
abstract::Several of the song control nuclei of songbirds, including HVc (higher vocal center) and Area X, contain melatonin receptor (MelR). In laboratory-housed male starlings, the densities of MelR in Area X change markedly according to reproductive state. MelR are down-regulated when starlings are photostimulated (in full b...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/s0016-6480(03)00261-2
更新日期:2003-11-01 00:00:00
abstract::The importance of late winter pairing activity on the neuroendocrinology of wild waterfowl is unknown. In this study, we examined the sex-related differences in the roles of late winter pairing activity and seasonal influences on neuroendocrine and reproductive physiology in both male and female mallards. Our main goa...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.2000.7469
更新日期:2000-05-01 00:00:00
abstract::The presence of a robust estrogen (E2) response system throughout heart and blood vessel tissues of vertebrates, including humans, has led to the speculation that this ubiquitous hormone may play a prominent role in the health and maintenance of the adult cardiovascular system (CVS). We previously established an embry...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2013.04.016
更新日期:2013-08-01 00:00:00
abstract::Male bluegill (Lepomis macrochirus) display a complex reproductive behavior involving two alternative life history pathways: delay of sexual maturation to become "parentals" or precocious maturation as "cuckolders." The purpose of our study was to investigate the association of two androgens, 11-ketotestosterone (11KT...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(89)90180-9
更新日期:1989-09-01 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