Endocrinology Commons^™

Canine Testes Thin Sections Culture​, Nguyen Khoi Nguyen, Ramanpreet Singh

2023 Symposium

Canine testes thin section culture

Testes tissue culture systems would provide a tool to elucidate spermatogenesis mechanisms, with the aim of genetic preservation of mammals, especially endangered species. Our experiment aims to develop a culture system capable of producing viable mammalian sperm cells in vitro.

Dogs were chosen as the model organism because testes are readily available. Canine testes were obtained from a local veterinary clinic. Thin sections were generated using a commercial electric slicer. They then were cleaned using Dulbecco’s Phosphate-Buffered Saline (DPBS) supplemented with antibiotics then cultured in a modified Tissue Culture Medium 199 (TCM-199). Sections were …

Canine Testes Thin Sections Culture, Nguyen Khoi Nguyen, Ramanpreet Singh

2023 Symposium

Canine testes thin section culture

Testes tissue culture systems would provide a tool to elucidate spermatogenesis mechanisms, with the aim of genetic preservation of mammals, especially endangered species. Our experiment aims to develop a culture system capable of producing viable mammalian sperm cells in vitro.

Dogs were chosen as the model organism because testes are readily available. Canine testes were obtained from a local veterinary clinic. Thin sections were generated using a commercial electric slicer. They then were cleaned using Dulbecco’s Phosphate-Buffered Saline (DPBS) supplemented with antibiotics then cultured in a modified Tissue Culture Medium 199 (TCM-199). Sections were …

Invited Review: Adrenocortical Function In Avian And Non-Avian Reptiles: Insights From Dispersed Adrenocortical Cells., Rocco V. Carsia, Patrick J. Mcilroy, Henry B John-Alder

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Herein we review our work involving dispersed adrenocortical cells from several lizard species: the Eastern Fence Lizard (Sceloporus undulatus), Yarrow's Spiny Lizard (Sceloporus jarrovii), Striped Plateau Lizard (Sceloporus virgatus) and the Yucatán Banded Gecko (Coleonyx elegans). Early work demonstrated changes in steroidogenic function of adrenocortical cells derived from adult S. undulatus associated with seasonal interactions with sex. However, new information suggests that both sexes operate within the same steroidogenic budget over season. The observed sex effect was further explored in orchiectomized and ovariectomized lizards, some supported with exogenous testosterone. Overall, a suppressive effect of testosterone was evident, especially in cells …

Prenatal Aromatase Inhibition Alters Postnatal Immunity In Domestic Chickens (Gallus Gallus), Jeff W. Simkins, Abby E. Joseph, Frances Bonier, Z. Morgan Benowitz-Fredericks

Faculty Journal Articles

In birds, exposure to exogenous testosterone during embryonic development can suppress measures of immune function; however, it is unclear whether these effects are due to direct or indirect action via aromatization. Estradiol (E2) is synthesized from testosterone by the enzyme aromatase, and this conversion is a necessary step in many signaling pathways that are ostensibly testosterone-dependent. Many lines of evidence in mammals indicate that E2 can affect immune function. We tested the hypothesis that some of the immunomodulatory effects observed in response to in ovo testosterone exposure in birds are mediated by conversion to E2 by aromatase, by using fadrozole …

Deciphering The Consequences Of Yolk Testosterone Metabolism In Birds, Nicole A. Campbell

Theses and Dissertations

Maternal steroids transferred to eggs can elicit permanent effects on various aspects of offspring phenotype. Although, testosterone was thought to be a key mediator of maternal effects in birds, we now know that vertebrate embryos actively regulate their exposure to maternal testosterone through steroid metabolism, suggesting testosterone metabolites may elicit the observed phenotypic effects. To address the role steroid metabolism plays in mediating yolk testosterone effects, we used European starling (Sturnus vulgaris) eggs to characterize the timing of testosterone metabolism and determine whether etiocholanolone, a prominent testosterone metabolite in avian embryos, is capable of influencing early embryonic development. Tritiated testosterone …

Early Contributions To Infants’ Mental Rotation Abilities, Mihaela Constantinescu, David S. Moore, Scott P. Johnson, Melissa Hines

Pitzer Faculty Publications and Research

Some cognitive abilities exhibit reliable gender differences, with females outperforming males in specific aspects of verbal ability, and males showing an advantage on certain spatial tasks. Among these cognitive gender differences, differences in mental rotation are the most robust, and appear to be present even in infants. A large body of animal research suggests that gonadal hormones, particularly testosterone, during early development could contribute to this gender difference in mental rotation. Also, substantial evidence supports an influence of socialization on mental rotation performance. The present study investigated the relationship of two types of factors, early postnatal testosterone exposure and parental …

Acute Salivary Steroid Hormone Responses During Coalitional And Dyadic Competitions In Hong Kong Juvenile Children, Timothy Mchale

UNLV Theses, Dissertations, Professional Papers, and Capstones

A large body of research links testosterone and cortisol responses to competition during adulthood. Little psychoneuroendocrine research has explored salivary steroid hormone responses to competition during middle childhood. This project investigated the relationship between acute salivary steroid hormone change, performance, competitor type, and outcome effects in three different field studies, while controlling for Body Mass Index (BMI) and pubertal development, in a population of ethnically Chinese, Hong Kong juvenile children, 8-11 years of age. The relative dynamics of salivary steroid change were assessed during a 1) coalitional physical competition (soccer) in boys, 2) a non-physical mixed-sex coalitional competition (math contest), …

Using A Mouse Model To Investigate Male Bias In Autism Spectrum Disorder Incidence., Elizabeth Ann Gordon

Electronic Theses and Dissertations

The review (Chapter 1) overviews our current understanding of the sex bias in autism spectrum disorders (ASD), whereby males are 4 times more likely to develop the condition. The longstanding uncertainty surrounding the etiology of autism can be informed by inclusion of both sexes in future research to better understand the mechanism responsible for this sex bias. Both clinical studies and animal models are useful tools to elucidate the underlying cause(s) of sexual dimorphic morphological, physiological, and behavioral differences in the ASD phenotype. Sex differences in social behaviors are common across species, underscoring the importance of assessing baseline sex differences …

Transition Between Phases Of The Annual Cycle: Spring Migration To Breeding In Nearctic-Neotropical Songbirds, Kristen Marie Covino

Dissertations

Appropriate timing of each life-history stage is crucial for seasonally migratory species. The temporal constraints faced by migratory songbirds require that they overlap preparation for breeding with spring migration. However, previous work has focused primarily on male birds and has produced inconsistent results regarding the degree of overlap between these two life-history stages. I study the degree to which migrating male and female songbirds prepare for breeding throughout spring migration as they move towards their breeding grounds. Overall, male migrants show a significant degree of breeding preparation during spring migration as determined by circulating testosterone levels and their ability to …

Lh-Independent Testosterone Secretion Is Mediated By The Interaction Between Gnrh2 And Its Receptor Within Porcine Testes, Amy T. Desaulniers, Rebecca A. Cederberg, Ginger A. Mills, J. Joe Ford, Clay A. Lents, Brett R. White

Department of Animal Science: Faculty Publications

Unlike classic gonadotropin-releasing hormone 1 (GNRH1), the second mammalian isoform (GNRH2) is an ineffective stimulant of gonadotropin release. Species that produce GNRH2 may not maintain a functional GNRH2 receptor (GNRHR2) due to coding errors. A full-length GNRHR2 gene has been identified in swine, but its role in reproduction requires further elucidation. Our objective was to examine the role of GNRH2 and GNRHR2 in testicular function of boars. We discovered that GNRH2 levels were higher in the testis than in the anterior pituitary gland or hypothalamus, corresponding to greater GNRHR2 abundance in the testis versus the anterior pituitary gland. Moreover, GNRH2 …

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 Relationship Between 11-Ketotestosterone, Cortisol, And Testosterone And Condition Index For Poecilia Reticulata, Shelly Gupta, Brandy G. Kalbach

Biological Sciences

The guppy, Poecilia reticulata, is a common study organism for behavioral and other ecological experiments (Houde, 1997).  As far as we know, no previous data have been compiled regarding hormones and condition index of guppies.  In this experiment we examined the relationship between circulating levels of three hormones (testosterone, 11-ketotestosterone and cortisol) and condition index in males and also made comparisons among the hormone levels, for three guppy sites from the northern range of Trinidad – Aripo River, Marianne River and Small Crayfish River.  Hormone samples were obtained using non-invasive water borne techniques and quantified by our collaborator.  The condition …

Flank Gland-Secreted Putative Chemosignals Pertaining To Photoperiod, Endocrine States, And Sociosexual Behavior In Golden Hamsters, Ying-Juan Liu, Da-Wei Wang, Lixing Sun, Jin-Hua Zhang, Jian-Xu Zhang

All Faculty Scholarship for the College of the Sciences

Behavioral studies have shown that flank glands are involved in chemical communication in golden hamsters Mesocricetus auratus but little chemical analysis has been conducted on volatiles arising from these glands. Using gas chromatography- mass spectrometry, we detected compounds from the flank glands of males, only eight of which were also produced in females. Based on these chemical data we performed a number of further experiments. By manipulating light we found that males exposed to short-photoperiods developed smaller flank glands than those exposed to long-photoperiods. Six flank gland volatiles reduced in relative abundance, which possibly coded for reproductive status of males …

Physiological Effects On Demography: A Long‐Term Experimental Study Of Testosterone’S Effects On Fitness, W. Reed, M. Clark, P. Parker, S. Raouf, N. Arguedas, D. Monk, E. Snajdr, V. Nolan, E. Ketterson

Biology Department Faculty Works

Understanding physiological and behavioral mechanisms underlying the diversity of observed life‐history strategies is challenging because of difficulties in obtaining long‐term measures of fitness and in relating fitness to these mechanisms. We evaluated effects of experimentally elevated testosterone on male fitness in a population of dark‐eyed juncos studied over nine breeding seasons using a demographic modeling approach. Elevated levels of testosterone decreased survival rates but increased success of producing extra‐pair offspring. Higher overall fitness for testosterone‐treated males was unexpected and led us to consider indirect effects of testosterone on offspring and females. Nest success was similar for testosterone‐treated and control males, …