Abstract：
:This study characterizes the seasonal reproductive cycle of female round stingrays (Urobatis halleri) in an open coastal site at Seal Beach, CA and a protected estuary at the Seal Beach National Wildlife Refuge (SBNWR). Female round stingrays were sampled from August 2004 to July 2006, and assessed for reproductive parameters (GSI, maximum ova diameter, pregnancy status) and sex steroid (estradiol (E(2)), progesterone (P(4)) and testosterone (T)) concentrations. E(2) and P(4) increased at the time of ovulation (June and July) and remained elevated until parturition (October and November); recently partruded females were observed until November. Mature females were absent from Seal Beach in August and September, the same time period that abundance of mature females peaked in the SBNWR. This aggregation of predominantly mature females in the upper reaches of the SBNWR was seasonal, and was observed from April to September. To better understand the aggregation behavior, sex steroid hormones were assayed in SBNWR females. In July and August, E(2) and P(4) concentrations in females at the SBNWR were 1.5-fold and 2-fold higher, respectively, than concentrations in mature females at Seal Beach, and correlated with elevated water temperature in the estuary. Pregnancy was confirmed in aggregating females by increased levels of E(2) and P(4) and the presence of developing embryos. Our data suggest that coastal estuaries may play a crucial role in round stingray reproduction, perhaps by providing a thermal refuge for pregnant females during gestation.
journal_name
Gen Comp Endocrinoljournal_title
General and comparative endocrinologyauthors
Mull CG,Lowe CG,Young KAdoi
10.1016/j.ygcen.2009.12.009subject
Has Abstractpub_date
2010-04-01 00:00:00pages
379-87issue
2eissn
0016-6480issn
1095-6840pii
S0016-6480(09)00436-5journal_volume
166pub_type
杂志文章abstract：:Catechol-O-methyltransferase (COMT) is involved in the methylation and inactivation of endogenous and xenobiotic catechol compounds, and serves as a common biochemical link in the catecholamine and catecholestrogen metabolism. Studies on cloning, sequencing and function characterization comt gene in lower vertebrates ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2016.12.001
更新日期：2017-05-15 00:00:00
abstract：:The effects of epinephrine (E), norepinephrine (NE), phenylephrine (PHE), and isoproterenol (ISO) were studied in vivo on the blood pressure and heart rate of the conscious American bullfrog, Rana catesbeiana. Bullfrogs were chronically cannulated with a T cannula in the right sciatic artery. In warm-acclimated (22 de...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(85)90401-0
更新日期：1985-09-01 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：:Natriuretic peptide type C (NPPC) and its receptor, natriuretic peptide receptor 2 (NPR2), have essential roles in maintaining meiotic arrest of oocytes in several mammalian species. However, it is not known if a similar mechanism exists in non-mammalian vertebrates. Using zebrafish as a model, we show that Nppc is ex...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2018.03.024
更新日期：2018-09-01 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：:Reproduction of many temperate fishes is seasonal and maturation and spawning of gametes are under photothermal control. Reproductive success of first generation (G1) common sole Solea solea in captivity has been low. In this study, the sexual maturation status has been assessed during the prespawning months in G1 sol...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2014.12.004
更新日期：2015-09-15 00:00:00
abstract：:The present study examined plasma concentrations of insulin-like growth factor (IGF)-I, IGF-II and IGF-binding proteins (IGFBPs) during posthatch growth and development in chickens. Three distinct proteins which bound 125I-IGF-I were observed irrespective of age or sex, these having apparent molecular weights of 22, 2...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1997.6898
更新日期：1997-07-01 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：:This study was conducted at the Bukhara breeding centre (Ouzbekistan, Central Asia) on Persian gazelles (Gazella subgutturosa subgutturosa) and at Thumammah (Saudi Arabia) on sand gazelles (Gazella subgutturosa marica). Plasma prolactin (PRL) and progesterone were determined in groups of females. Because these females...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.2000.7561
更新日期：2001-01-01 00:00:00
abstract：:Using frog ovarian follicles in vitro we assessed the role of the theca/epithelium (THEP) layer and granulosa cells in the production of steroids. The THEP layer and granulosa cell-enclosed oocytes (GCEOs) were separated from ovarian follicles of the frog, Rana nigromaculata, by microdissection. Intact follicles (IFs)...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1994.1077
更新日期：1994-05-01 00:00:00
abstract：:In goldfish, plasma gonadotropin levels increase during spawning in both males and females (GTH surge). A female-typical GTH surge induces ovulation (ovulatory surge), and a male-typical surge triggers milt production in response to sex pheromones released from ovulatory females. This study examined whether the male-t...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1997.6993
更新日期：1997-12-01 00:00:00
abstract：:Although present at relatively low number in the testis, spermatogonial stem cells (SSCs) are crucial for the establishment and maintenance of spermatogenesis in eukaryotes and, until recently, those cells were investigated in fish using morphological criteria. The isolation and characterization of these cells in fish...
journal_title：General and comparative endocrinology
pub_type： 杂志文章,评审
doi：10.1016/j.ygcen.2014.06.018
更新日期：2014-10-01 00:00:00
abstract：:A highly specific and homologous radioimmunoassay (RIA) for the measurement of prolactin (PRL) in the plasma and the pituitary of the eel was developed using a rabbit antiserum to eel PRL. PRL was purified from the pituitary of Japanese eel (Anguilla japonica). Pituitary extracts and plasma from the Japanese and Europ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(91)90167-5
更新日期：1991-03-01 00:00:00
abstract：:The development and dynamics of TSH and GTH cells were studied immunohisto- and immunocytochemically in the salamander Hynobius retardatus, which had been reported to show neoteny in a specific environment and a precocious development and maturation of testis in goitrogen-treated larvae. Pituitary glands from normally...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1996.0172
更新日期：1996-12-01 00:00:00
abstract：:Abnormalities in calcium (Ca(2+)) homeostasis are reported in horses with several pathological conditions; however, there is little information on Ca(2+) regulation in horses. The objectives of the present study were to determine the Ca(2+) set-point in healthy horses, to determine whether the Ca(2+)/parathyroid hormo...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/s0016-6480(02)00621-4
更新日期：2003-02-15 00:00:00
abstract：:We demonstrated the presence of specific binding sites for bullfrog luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in a testicular crude plasma membrane fraction of the bullfrog, Rana catesbeiana. The equilibrium analysis of the binding showed that a straight line was fitted to the Scatchard plot of L...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(86)90207-8
更新日期：1986-02-01 00:00:00
abstract：:Effects of fasting on the growth hormone (GH)--growth hormone receptor (GHR)-insulin-like growth factor-I (IGF-I) axis were characterized in seawater-acclimated tilapia (Oreochromis mossambicus). Fasting for 4 weeks resulted in significant reductions in body weight and specific growth rate. Plasma GH and pituitary GH ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2006.04.007
更新日期：2006-09-15 00:00:00
abstract：:To understand how the social and physical environment influences behaviour, reproduction and survival, studies of underlying hormonal processes are crucial; in particular, interactions between stress and reproductive responses may have critical influences on breeding schedules. Several authors have examined the timing...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2011.05.006
更新日期：2011-08-01 00:00:00
abstract：:This study investigates the effects of exogenous thyroxine (T4) on running endurance, tissue masses, and the activities of citrate synthase (CS), pyruvate kinase (PK), cytosolic alpha-glycerophosphate dehydrogenase (alpha-GPDH), and beta-hydroxyacyl Coenzyme A dehydrogenase (HOAD) in Sceloporus undulatus (eastern fenc...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(91)90132-p
更新日期：1991-01-01 00:00:00
abstract：:Birds use both the corticosterone stress response and immune system to meet physiological challenges during exposure to adverse climatic conditions. To assess the stress level and immune response of the Asian Great Bustard during conditions of severe winter weather, we measured fecal corticosterone (CORT) and Immunogl...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2018.02.014
更新日期：2018-05-15 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
abstract：:Changes in the pituitary cells involved in amphibian metamorphosis were studied in Bufo arenarum tadpoles with inhibited thyroid function. After hatching, larvae were treated for 5 months with potassium perchlorate (KClO4), a goitrogenic substance known to prevent absorption of iodine from water or food, resulting in ...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1995.1057
更新日期：1995-05-01 00:00:00
abstract：:The isolation of a maturational gonadotropin from pituitaries of Atlantic croaker (Micropogonias undulatus), a marine teleost belonging to the order perciformes, is described. A radioimmunoassay has been developed for the measurement of this hormone in blood samples and validation of the assay is presented. The hormon...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/0016-6480(89)90200-1
更新日期：1989-03-01 00:00:00
abstract：:Arsenic contaminates water surface and groundwater worldwide. Several studies have suggested that arsenic acts as an endocrine disruptor in mammalian and non-mammalian species, although its chronic effect during development remains largely unknown. To address this question, life cycle exposures to 0, 0.3 and 0.8ppm of...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2015.09.015
更新日期：2016-08-01 00:00:00
abstract：:Myostatin (GDF-8) inhibits the activation, proliferation, and differentiation of myogenic satellite cells. The relative importance of this growth factor is demonstrated in myostatin-null mice and cattle possessing defective myostatin genes. These defects result in greatly enhanced musculature. In the present study, th...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2007.02.006
更新日期：2007-05-01 00:00:00
abstract：:The present investigation was designed to (1) determine if atrial natriuretic factor gene expression occurs within invertebrates as well as within vertebrates; (2) determine whether the product of this gene expression is the 126-amino-acid atrial natriuretic factor prohormone or some other molecular species; and (3) e...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1006/gcen.1995.1133
更新日期：1995-10-01 00:00:00
abstract：:The objectives of this study were to investigate the seasonal changes in pituitary gonadotropins, growth hormone (GH), and estrogen receptor (ER) isoform mRNA in wild female and male largemouth bass (LMB) (Micropterus salmoides) from an unpolluted habitat to better understand reproductive physiology in this ecological...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2009.04.028
更新日期：2009-09-15 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：: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：:Stress-induced inhibition of innate immune activity has been observed in a variety of wild birds and may increase chances of infection because this activity constitutes the first line of defense against pathogens. We previously reported that the transient elevation of plasma corticosterone (CORT; the primary avian glu...
journal_title：General and comparative endocrinology
pub_type： 杂志文章
doi：10.1016/j.ygcen.2019.02.002
更新日期：2019-05-01 00:00:00
