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Endocrinology Commons

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2014

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Articles 1 - 10 of 10

Full-Text Articles in Endocrinology

Exploring The Glucocorticoid Actions Of 1Α-Hydroxycorticosterone (1Α-Oh-B) In The Elasmobranch Fishes, Faith Nichole Lambert Dec 2014

Exploring The Glucocorticoid Actions Of 1Α-Hydroxycorticosterone (1Α-Oh-B) In The Elasmobranch Fishes, Faith Nichole Lambert

Master's Theses

The corticosteroid 1α-hydroxycorticosterone (1α-OH-B) is unique to the elasmobranch fishes. It is thought that 1α-OH-B acts as both the primary glucocorticoid (GC) and mineralocorticoid (MC) in these fishes, a dual role analogous to that of cortisol in the teleost fishes. The MC characteristics of 1α-OH-B are well supported, but data supporting its GC functions are lacking. In this study, the putative GC actions of 1α-OH-B were examined. The first experiment characterized the physiological stress response of the Atlantic stingray (Dasyatis sabina) to air exposure, with particular regards to the roles of corticosteroids and metabolic fuels. Results demonstrate that …


Functional Characterization Of The Arginine Vasotocin 4 Receptor (Vt4r) In Sensory Circumventricular Organs Of The Chicken Gallus Gallus, Nguiessan Alphonse Aman Dec 2014

Functional Characterization Of The Arginine Vasotocin 4 Receptor (Vt4r) In Sensory Circumventricular Organs Of The Chicken Gallus Gallus, Nguiessan Alphonse Aman

Graduate Theses and Dissertations

Past studies have shown that the avian vasotocin 4 receptor (VT4R), homologous to the mammalian arginine vasopressin receptor 1a (V1aR/AVPR1A) is involved in immobilization stress. It was not known, however, whether the receptor is also associated with osmotic stress, and if so, what brain regions may be involved. Four treatment groups of chicks were used for the study. One group was subjected to 1h immobilization stress and two groups were administered intraperitoneal injection of 3 M NaCl or 0.15 M NaCl. One additional group served as controls. After 1 h, blood samples were taken for the determination of plasma levels …


Family Of Flp Peptides In Caenorhabditis Elegans And Related Nematodes, Chris Li, Kyuhyung Kim Oct 2014

Family Of Flp Peptides In Caenorhabditis Elegans And Related Nematodes, Chris Li, Kyuhyung Kim

Publications and Research

Neuropeptides regulate all aspects of behavior in multicellular organisms. Because of their ability to act at long distances, neuropeptides can exert their effects beyond the conventional synaptic connections, thereby adding an intricate layer of complexity to the activity of neural networks. In the nematode Caenorhabditis elegans, a large number of neuropeptide genes that are expressed throughout the nervous system have been identified.The actions of these peptides supplement the synaptic connections of the 302 neurons, allowing for fine tuning of neural networks and increasing the ways in which behaviors can be regulated. In this review, we focus on a large …


The Effect Of Maternal Aldosterone Levels On The Expression Of 11b-Hsd Isoenzymes In Normal And Hypertensive Rat Placentae, Nicole Jorissen Aug 2014

The Effect Of Maternal Aldosterone Levels On The Expression Of 11b-Hsd Isoenzymes In Normal And Hypertensive Rat Placentae, Nicole Jorissen

Journal of Undergraduate Research at Minnesota State University, Mankato

In this project, we developed a Western blotting procedure to semi-quantitate levels of 11β-HSD1 and 11β-HSD2 in whole cell extracts. Then, we applied this technique to analyze the effect of reduced maternal aldosterone levels on the expression of 11β-HSD1 and 11β-HSD2 isoenzymes in the placental tissue in both normal and hypertensive rats. These enzymes control levels of glucocorticoids which compete for aldosterone’s mineralocorticoid receptor. Overstimulation of this receptor results in hypertension. If aldosterone levels decrease, levels of the enzymes controlling active glucocorticoid concentrations might change to compensate for the lowered aldosterone levels. Decreased placental 11β-HSD2 expression could affect hypertension in …


Influence Of Steroids And Gonadotropins On Reproduction In Beef Cattle, Thomas L. Devine Aug 2014

Influence Of Steroids And Gonadotropins On Reproduction In Beef Cattle, Thomas L. Devine

Graduate Theses and Dissertations

The objective of this thesis was to evaluate the influence of steroids and gonadotropins on reproduction in beef cattle. In experiment 1, beef heifers were used to determine the influence of growth-promoting implants on growth, reproductive development, estrous behavior, and pregnancy rate. Heifers were assigned to 1 of 4 implant treatment groups: control (CON); trenbolone acetate (TBA); trenbolone acetate plus estradiol (TBA+E2) or zeranol (ZER). Heifers were implanted once, A.I. and exposed to bull during this experiment. Body weight, BCS, HH, RTS, estrous behavior and pregnancy data were collected throughout this experiment. Average daily gain of heifers was greater for …


Vitamin A Deficiency Causes Ovulation Abnormalities In Mice, Rebecca Ursin Jun 2014

Vitamin A Deficiency Causes Ovulation Abnormalities In Mice, Rebecca Ursin

DePaul Discoveries

Retinoic acid (RA) is an active metabolite of vitamin A (VA) and is involved in tissue organization, patterning, and growth. RA has been shown to regulate male reproduction, however information on its role in ovary development is limited. To investigate the functions of RA in the ovary, we examined its role in ovary development and ovulation using an in vivo dietary VA-deprivation animal model. Our preliminary results have shown that VA deficiency causes a variety of ovarian pathologies, including reduced numbers of total follicles and corpus lutea, formation of hemorrhagic and atretic follicles, and formation of bursa and follicular cysts. …


Phthalates And Phthalate Alternatives: Effects On Proliferative And Estrogenic Target Genes In Ishikawa Cells, Ranjani Sundar '15, Ping Yin, Serdar E. Bulun May 2014

Phthalates And Phthalate Alternatives: Effects On Proliferative And Estrogenic Target Genes In Ishikawa Cells, Ranjani Sundar '15, Ping Yin, Serdar E. Bulun

Student Publications & Research

Phthalates are used as plasticizers in many of the products found in medical, household, and industrial applications. Much research has not been completed on the effects of these phthalates as potential endocrine disrupting chemicals (EDCs). As these chemicals are ingested, the mechanism by which they affect the reproductive system is largely unknown. The purpose of this study was to observe how 2 phthalates, Di-n-butyl phthalate (DBP) and Diisononyl phthalate (DINP), and 2 phthalate alternatives, Dioctyl terephthalate (DOTP) and BHT (butylated hydroxytoluene)affect uterine cells in comparison to a vehicle treatment and 17β-Estradiol treatment. Changes in expression of mRNA were observed using …


Self-Construal Moderates Testosterone Reactivity To Competitive Outcomes, Keith Welker Jan 2014

Self-Construal Moderates Testosterone Reactivity To Competitive Outcomes, Keith Welker

Wayne State University Dissertations

Previous research shows that testosterone reactivity to competitive outcomes predicts aggressive behavior in men. However, some studies have failed to find these effects, and it has been suggested that individual differences moderate the relationships between competitive outcomes, testosterone fluctuations, and aggressive behavior. The current research examined whether one individual difference--self-construal--would moderate these effects. In Study 1, participants were assigned to win or lose a competitive video game and engaged in a reactive aggression task. Results indicated that increases in testosterone in response to winning and decreases in response to losing occurred in men with independent, not interdependent, self-construals. These changes …


The Effects Of Stress Hormones On Preferences For Acoustic Signals In Female Green Treefrogs (Hyla Cinerea) And Barking Treefrogs (Hyla Gratiosa), Anna Gabriell Davis Jan 2014

The Effects Of Stress Hormones On Preferences For Acoustic Signals In Female Green Treefrogs (Hyla Cinerea) And Barking Treefrogs (Hyla Gratiosa), Anna Gabriell Davis

Electronic Theses and Dissertations

Ecological stressors (i.e., high predator density, low food availability) are often associated with increased variation in mate choice by females. The association between environmental stressors and variation in mate choice suggests that circulating stress hormones (i.e., glucocorticoids) may mediate such effects, but this idea remains largely unexplored. I examined how circulating glucocorticoids affect preferences for male advertisement calls in female green treefrogs, Hyla cinerea, and barking treefrogs, Hyla gratiosa. Specifically, I examined whether administration of corticosterone (CORT) decreases preferences for call rate and/or call duration - two acoustic features that are highly variable and characteristically under directional selection via mate …


Regulation Of Pancreatic Α And Β Cell Function By The Bile Acid Receptor Tgr5, Divya Prasanna Kumar Jan 2014

Regulation Of Pancreatic Α And Β Cell Function By The Bile Acid Receptor Tgr5, Divya Prasanna Kumar

Theses and Dissertations

The discovery that bile acids act as endogenous ligands of the membrane receptor TGR5 and the nuclear receptor FXR increased their significance as regulators of cholesterol, glucose and energy metabolism. Activation of TGR5, expressed on enteroendocrine L cells, by bile acids caused secretion of GLP-1, which stimulates insulin secretion from pancreatic β cells. Expression of TGR5 on pancreatic islet cells and the direct effect of bile acids on the endocrine functions of pancreas, however, are not fully understood. The aim of this study was to identify expression of TGR5 in pancreatic islet cells and determine the effect of bile acids …