journal
MENU ▼
Read by QxMD icon Read
search

General and Comparative Endocrinology

journal
https://www.readbyqxmd.com/read/28212895/the-influence-of-enteral-obestatin-administration-to-suckling-rats-on-intestinal-contractility
#1
M Słupecka, P Grzesiak, J Kwiatkowski, M Gajewska, A Kuwahara, I Kato, J Woliński
This study investigated the effect of enteral administration of obestatin on the contractility of whole-thickness preparations of duodenum and middle jejunum, as well as on the morphology of the enteric nervous system (ENS). Suckling rats were assigned to 3 groups (n=12) treated with: C- saline solution; LO- obestatin (125 nmol/kg b.wt); HO-obestatin (250 nmol/kg b.wt). Saline solution or obestatin were administered twice daily, from the 14(th) to the 21(st) day of life. Sections were studied in an organ bath, for isometric recording in the presence of acetylocholine (ACh), atropine (ATR) and tetradotoxin (TTX)...
February 14, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28212894/exogenous-thyroid-hormones-regulate-the-activity-of-citrate-synthase-and-cytochrome-c-oxidase-in-warm-but-not-cold-acclimated-lake-whitefish-coregonus-clupeaformis
#2
Megan A Zak, Amy M Regish, Stephen D McCormick, Richard G Manzon
Thermal acclimation is known to elicit metabolic adjustments in ectotherms, but the cellular mechanisms and endocrine control of these shifts have not been fully elucidated. Here we examined the relationship between thermal acclimation, thyroid hormones and oxidative metabolism in juvenile lake whitefish. Impacts of thermal acclimation above (19 °C) or below (8 °C) the thermal optimum (13 °C) and exposure to exogenous thyroid hormone (60 µg T4/g body weight) were assessed by quantifying citrate synthase and cytochrome c oxidase activities in liver, red muscle, white muscle and heart...
February 14, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28189591/sex-hormone-binding-globulin-expression-throughout-early-development-and-adult-pejerrey-fish-odontesthes-bonariensis
#3
Anelisa González, Juan I Fernandino, Geoffrey L Hammond, Gustavo M Somoza
Sex hormone binding globulin (Shbg) is a plasma glycoprotein that binds and transports steroids in the blood of all vertebrate classes apart from birds. In the present study we characterized shbg from pejerrey, a fish species with a well characterized temperature-dependent sex determination. The pejerrey shbg mRNA comprises 1185bp encoding for a 395 amino acid Shbg precursor protein that includes a leader sequence for secretion. Relative quantification of shbg transcript abundance revealed expression early in development coinciding with the sex-determining period and probably in association with temperature leading to male determination...
February 9, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28189590/stress-responsiveness-influences-baseline-glucocorticoid-levels-revisiting-the-under-3-min-sampling-rule
#4
Thomas W Small, Sara E Bebus, Eli S Bridge, Emily K Elderbrock, Stephen M Ferguson, Blake C Jones, Stephan J Schoech
Plasma glucocorticoid (CORT) levels collected within 3 min of capture are commonly believed to reflect pre-stressor, baseline CORT levels. Differences in these "baseline" values are often interpreted as reflecting differences in health, or the amount of social and environmental stress recently experienced by an individual. When interpreting "baseline" values it is generally assumed that any effect of capture-and-handling during the initial sampling period is small enough and consistent enough among individuals to not obscure pre-capture differences in CORT levels...
February 8, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28188743/primary-males-guide-the-femaleness-through-the-regulation-of-testicular-dmrt1-and-ovarian-cyp19a1a-in-protandrous-black-porgy
#5
REVIEW
Guan-Chung Wu, Ching-Fong Chang
Controlling the development of the sexes is critically important for the broodstock management in aquaculture. Sex steroids are widely used for sex control of fish. However, hermaphroditic fish have a plastic sex, and a stable sex is difficult to maintain with sex steroids. We used the black porgy (Acanthopagrus schlegelii) as a model to understand the possible mechanism of sexual fate decision. Low exogenous estradiol (E2) induced male development. In contrast, high exogenous E2 induced the regression of the testis and the development of the ovary and resulted in an unstable expression of femaleness (passive femaleness, with ovaries containing only the primary oocytes)...
February 7, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28185936/why-goldfish-merits-and-challenges-in-employing-goldfish-as-a-model-organism-in-comparative-endocrinology-research
#6
Ayelén Melisa Blanco, Lakshminarasimhan Sundarrajan, Juan Ignacio Bertucci, Suraj Unniappan
Goldfish has been used as an unconventional model organism to study a number of biological processes. For example, goldfish is a well-characterized and widely used model in comparative endocrinology, especially in neuroendocrinology. Several decades of research has established and validated an array of tools to study hormones in goldfish. The detailed brain atlas of goldfish, together with the stereotaxic apparatus, are invaluable tools for the neuroanatomic localization and central administration of endocrine factors...
February 7, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28185935/progesterone-transfer-among-cohabitating-female-big-brown-bats-eptesicus-fuscus
#7
Lucas J Greville, Tyler Pollock, Joseph C Salter, Paul A Faure, Denys deCatanzaro
Experiments using female mice and bats have demonstrated that tritium-labeled 17β-estradiol ((3)H-E2) can be absorbed via cutaneous and intranasal routes and distributed to reproductive and neural tissues. Radioactivity has also been measured in tissues of untreated females after 48h cohabitation with (3)H-E2 injected males. The present study was designed to quantify steroid transfer among female bats. Radioactive quantification via liquid scintillation counting revealed absorption of tritium-labeled progesterone ((3)H-P4) in adult females 1h after cutaneous and intranasal application (10μCi)...
February 7, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28185934/corticosteroids-deeply-depress-the-in-vitro-steroidogenic-capacity-of-eurasian-perch-ovary-at-the-end-of-the-reproductive-cycle
#8
S N M Mandiki, S Milla, S Nkogo Robles, P Kestemont
Corticosteroids play positive or negative role in the reproductive mechanisms of many fish species but the physiological contexts relating to such biphasic actions are not well defined. In the present study we investigated to what extent corticosteroids (cortisol-Co, 11-deoxycorticosterone-DOC) hormones may interfere with the steroidogenic capacity of Eurasian perch follicles, and we tested whether the negative interference of corticosteroids may be mitigated by potential stimulating endocrine factors, namely insulin-like growth factor-1 (IGF), human chorionic gonadotropin (HCG) or thyroid hormones (Triidothyronine-T3, thyroxine-T4)...
February 6, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28174130/identification-and-expression-of-nuclear-receptor-genes-and-ecdysteroid-titers-during-nymphal-development-in-the-spider-agelena-silvatica
#9
Yoshiko Honda, Wataru Ishiguro, Mari H Ogihara, Hiroshi Kataoka, DeMar Taylor
Ecdysteroids play an essential role in the regulation of the molting processes of arthropods. Nuclear receptors of the spider Agelena silvatica that showed high homology with other arthropods especially in the functional domains were identified, two isoforms of ecdysone receptor (AsEcRA, AsEcRB), retinoid X receptor (AsRXR) and two isoforms of E75 (AsE75A, AsE75D). AsEcR and AsRXR mRNA did not show major changes in expression but occurred throughout the third instar nymphal stage. AsE75DBD was low or non-existent at first then showed a sudden increase from D7 to D10...
February 4, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28161438/molecular-and-evolutionary-perspectives-of-the-renin-angiotensin-system-from-lamprey
#10
Marty K S Wong, Yoshio Takei
The recent advance and revision on the renin-angiotensin system in lamprey were summarized and we emphasized that presence of two types of angiotensins (Angs) in lamprey. Due to the parasitic nature on fish blood, teleost-type Angs were produced in their buccal gland and secreted into the lamphredin to evade the host immunorejection. A native lamprey angiotensinogen (AGT) was identified in genome and it retains serine-protease inhibitor activity for thrombin that regulates the blood coagulation pathway. The native lamprey angiotensin II (Lp-Ang II) is hypotensive instead of hypertensive, suggesting a functional divergence on cardiovascular regulation from the main vertebrate groups...
February 2, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28161439/lipid-signaling-and-fat-storage-in-the-dark-eyed-junco
#11
Jacqueline M Ho, Christine M Bergeon Burns, Nikki M Rendon, Kimberly A Rosvall, Heather B Bradshaw, Ellen D Ketterson, Gregory E Demas
Seasonal hyperphagia and fattening promote survivorship in migratory and wintering birds, but reduced adiposity may be more advantageous during the breeding season. Factors such as photoperiod, temperature, and food predictability are known environmental determinants of fat storage, but the underlying neuroendocrine mechanisms are less clear. Endocannabinoids and other lipid signaling molecules regulate multiple aspects of energy balance including appetite and lipid metabolism. However, these functions have been established primarily in mammals; thus the role of lipid signals in avian fat storage remains largely undefined...
February 1, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28161437/tissue-organization-alters-gene-expression-in-equine-induced-trophectoderm-cells
#12
Brad M Reinholt, Jennifer S Bradley, Robert D Jacobs, Alan D Ealy, Sally E Johnson
Rapid morphological and gene expression changes occur during the early formation of a mammalian blastocyst. Critical to successful retention of the blastocyst and pregnancy is a functional trophectoderm (TE) that supplies the developing embryo with paracrine factors and hormones. The contribution of TE conformational changes to gene expression was examined in equine induced trophoblast (iTr) cells. Equine iTr cells were cultured as monolayers or in suspension to form spheres. The spheres are hollow and structurally reminiscent of native equine blastocysts...
February 1, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28153577/molecular-characterization-and-functional-analysis-of-pituitary-gnrh-receptor-in-a-commercial-scombroid-fish-chub-mackerel-scomber-japonicus
#13
Sanny David Pacheco Lumayno, Hirofumi Ohga, Sethu Selvaraj, Mitsuo Nyuji, Akihiko Yamaguchi, Michiya Matsuyama
The gonadotropin-releasing hormone (GnRH) is essential during pubertal onset, for its regulation of the synthesis and release of pituitary gonadotropins. Its action is mediated by GnRH receptors (GnRHRs) in the pituitary gonadotrophs. Our previous study demonstrated that the chub mackerel brain expresses three GnRH forms (gnrh1, gnrh2, and gnrh3), and that only GnRH1 neurons innervate anterior pituitary regions. Furthermore, chub mackerel gnrh1 mRNA exhibited a significant increase at pubertal onset. The present study aimed to isolate the functional GnRHR form involved in chub mackerel puberty...
January 30, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28137535/an-experimental-test-of-the-effect-of-brood-size-on-glucocorticoid-responses-parental-investment-and-offspring-phenotype
#14
Maren N Vitousek, Brittany R Jenkins, Joanna K Hubbard, Sara A Kaiser, Rebecca J Safran
Because elevated glucocorticoid levels can impair reproduction, populations or species that engage in particularly valuable reproductive attempts may down-regulate the glucocorticoid stress response during reproduction (the brood value hypothesis). It is not clear, however, whether individuals rapidly modulate glucocorticoid responses based on shifting cues about the likelihood of reproductive success. By manipulating brood size to create broods that differed in potential value, we tested whether female barn swallows (Hirundo rustica) rapidly modulated the glucocorticoid stress response to promote investment in high-value broods, and whether nestling phenotype was influenced by treatment...
January 28, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28132863/immune-endocrine-interactions-in-marsupials-and-monotremes
#15
E Peel, K Belov
Interactions between the immune and endocrine systems are not well studied in marsupials and monotremes. One exception to this is the phenomenon of semelparity, which is well covered in the literature as this is an unusual reproductive strategy amongst mammals and is only observed in some dasyurid and didelphid marsupials. Thymus involution provides a direct link between the endocrine and immune systems and warrants further study in marsupials and monotremes. The thymus is a primary immune tissue which is essential for overall immune function...
January 27, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28131616/how-is-gnrh-regulated-in-gnrh-producing-neurons-studies-using-gt1-7-cells-as-a-gnrh-producing-cell-model
#16
REVIEW
Haruhiko Kanasaki, Aki Oride, Tselmeg Mijiddorj, Unurjargal Sukhbaatar, Satoru Kyo
Hypothalamic secretion of gonadotropin-releasing hormone (GnRH) has been established as a principle pathway for initiating and integrating female reproductive function. GnRH stimulates the release of two gonadotropins-luteinizing hormone and follicle-stimulating hormone-from the anterior pituitary, which eventually stimulate the synthesis of sex steroids in association with follicular growth and ovulation. This reproductive control of the hypothalamic-pituitary-gonadal (HPG) axis also mediates gonadal feedback mechanisms...
January 25, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28126346/purification-and-identification-of-25-hydroxycholesterol-in-a-reptile-seasonal-variation-and-hormonal-regulation
#17
Varsha Singh, Manisha Priyam, Mamta Tripathy, Umesh Rai
The present in vitro study, for the first time, demonstrates the production of 25-hydroxycholestrol (25-HC) by testicular macrophages of a non-mammalian vertebrate. The ether extracts of testicular macrophage-conditioned medium (TMCM) were fractionated on a C18 reversed phase high-performance liquid chromatography (HPLC) column using methanol as the mobile phase. The mass spectrometry (MS) fragmentation pattern of HPLC-purified 25-HC was found to be identical to that of authentic 25-HC. Further, a significant seasonal variation in 25-HC concentration was observed with maximal level in regressed and minimal during breeding phase...
January 23, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28126345/regulation-of-plasma-glucose-and-sulfate-excretion-in-pacific-hagfish-eptatretus-stoutii-is-not-mediated-by-11-deoxycortisol
#18
Alexander M Clifford, Nicolas R Bury, Aaron G Schultz, James D Ede, Brendan L Goss, Greg G Goss
The goal of this study was to identify whether Pacific hagfish (Eptatretus stoutii) possess glucocorticoid and mineralocorticoid responses and to examine the potential role(s) of four key steroids in these responses. Pacific hagfish were injected with varying amounts of cortisol, corticosterone or 11-deoxycorticosterone (DOC) using coconut oil implants and plasma glucose and gill total-ATPase activity were monitored as indices of glucocorticoid and mineralocorticoid responses. Furthermore, we also monitored plasma glucose and 11-deoxycortisol (11-DOC) levels following exhaustive stress (30 min of agitation) or following repeated infusion with SO4(2-)...
January 23, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28126344/characterization-and-longitudinal-monitoring-of-serum-androgens-and-glucocorticoids-during-normal-pregnancy-in-the-killer-whale-orcinus-orca
#19
Todd R Robeck, Karen J Steinman, Justine K O'Brien
The secretory patterns of testosterone (T), androstenedione (A4), dehydroepiandrosterone (DHEA), cortisol (C), and corticosterone (Co) were characterized throughout 28 normal pregnancies until two-months post-partum in eleven killer whales. Effects of fetal sex, dam parity or age, and season were evaluated across either day post-conception (DPC), stage of pregnancy (PRE, EARLY, MID, LATE, POST) or indexed month post-conception (IMPC) using a mixed model linear regression with animal ID and pregnancy number as the random variables...
January 23, 2017: General and Comparative Endocrinology
https://www.readbyqxmd.com/read/28118985/mechanisms-of-modulation-of-the-egr-gene-family-in-mammary-epithelial-cells-of-different-species
#20
P Santino, E Martignani, S Miretti, M Baratta, P Accornero
In the adult female, within the estrous cycle, the mammary gland undergoes multiple rounds of growth, with increased cellular proliferation, and involution, with increased apoptosis. The increase in proliferation is elicited by endocrine (Estrogen, Progesterone), as well as locally produced (Epidermal growth factor, Insulin-like growth factor, etc) growth factors. Among the genes that are modulated during cellular proliferation, immediate early genes play a fundamental role, being rapidly upregulated and then downregulated within the G0/G1 phase of the cell cycle, allowing the progression to the subsequent phases...
January 21, 2017: General and Comparative Endocrinology
journal
journal
23401
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"