scholarly journals Epididymis Expresses the Highest 5′-Deiodinase Activity in the Male Reproductive System: Kinetic Characterization, Distribution, and Hormonal Regulation

Endocrinology ◽  
2008 ◽  
Vol 149 (8) ◽  
pp. 4209-4217 ◽  
Author(s):  
Brenda Anguiano ◽  
Nuri Aranda ◽  
Guadalupe Delgado ◽  
Carmen Aceves
Keyword(s):  
Reproductive System ◽  
Hormonal Regulation ◽  
Reproductive Tract ◽  
Pcr Amplification ◽  
Male Reproductive System ◽  
Reverse T3 ◽  
Physiological Relevance ◽  
Kinetic Pattern ◽  
And Function ◽  
Menten Constant

We characterized the enzymes that catalyze the deiodination of T4 to T3 in the male reproductive tract. Testis, epididymis (EPI), seminal vesicles, prostate, bulbourethral glands, spermatozoa, and semen were taken from sexually mature rats (300 g). Iodothyronine 5′-deiodinase (5′-D) activity was quantified by the radiolabeled-iodide-release method. 5′-D activity was 10-fold higher in EPI and semen than in the rest of the tissues. In EPI, semen, and prostate, the enzymatic activity was completely inhibited by 1 mm 6-n-propyl-2-thiouracil, whereas in the other tissues the inhibition was partial (50%). The high susceptibility to 6-n-propyl-2-thiouracil inhibition, a ping-pong kinetic pattern, and low cofactor (Michaelis Menten constant for dithiothreitol = 0.7 mm) and high substrate (Michaelis Menten constant for reverse T3 = 0.4 μm) requirements indicate that EPI 5′-D corresponds to type 1 deiodinase (D1). Real-time RT-PCR amplification of D1 mRNA in this tissue confirms this conclusion. The highest EPI D1 expression occurred at the onset of puberty and sexual maturity, and in the adult, this activity was more abundant in corpus and caput than in the caudal region. EPI D1 expression was elevated under conditions of hyperthyroidism and with addition of 17β-estradiol. Our data also showed a direct association between D1 and a functional epididymis marker, the neutral α-glucosidase enzyme, suggesting that local generation of T3 could be associated with the development and function of EPI and/or spermatozoa maturation. Further studies are necessary to analyze the possible physiological relevance of 5′-D in the male reproductive system.

scholarly journals The Concept of Male Reproductive Anatomy

2021 ◽  
Author(s):  
Oyovwi Mega Obukohwo ◽  
Nwangwa Eze Kingsley ◽  
Rotu Arientare Rume ◽  
Emojevwe Victor
Keyword(s):  
Reproductive System ◽  
Reproductive Tract ◽  
Prostate Gland ◽  
Ejaculatory Duct ◽  
Seminal Vesicles ◽  
Female Reproductive Tract ◽  
Male Reproductive System ◽  
Male Gametes ◽  
Human Reproductive ◽  
Reproductive Anatomy

The human reproductive system is made up of the primary and secondary organs, which helps to enhances reproduction. The male reproductive system is designed to produce male gametes and convey them to the female reproductive tract through the use of supportive fluids and testosterone synthesis. The paired testis (site of testosterone and sperm generation), scrotum (compartment for testis localisation), epididymis, vas deferens, seminal vesicles, prostate gland, bulbourethral gland, ejaculatory duct, urethra, and penis are the parts of the male reproductive system. The auxiliary organs aid in the maturation and transportation of sperm. Semen is made up of sperm and the secretions of the seminal vesicles, prostate, and bulbourethral glands (the ejaculate). Ejaculate is delivered to the female reproduc¬tive tract by the penis and urethra. The anatomy, embryology and functions of the male reproductive system are discussed in this chapter.

scholarly journals Estrogen receptors and function in the male reproductive system

2009 ◽  
Vol 53 (8) ◽  
pp. 923-933 ◽  
Author(s):  
Maria Fatima Magalhães Lazari ◽  
Thais Fabiana Gameiro Lucas ◽  
Fabiana Yasuhara ◽  
Gisele Renata Oliveira Gomes ◽  
Erica Rosanna Siu ◽  
...  
Keyword(s):  
Growth Factors ◽  
Estrogen Receptors ◽  
Reproductive System ◽  
Male Reproductive System ◽  
Estrogen Signaling ◽  
Nuclear Receptor Family ◽  
And Function ◽  
Rapid Signaling ◽  
G Protein Coupled ◽  
Receptor Family

A substantial advance in our understanding on the estrogen signaling occurred in the last decade. Estrogens interact with two receptors, ESR1 and ESR2, also known as ERα and ERβ, respectively. ESR1 and ESR2 belong to the nuclear receptor family of transcription factors. In addition to the well established transcriptional effects, estrogens can mediate rapid signaling, triggered within seconds or minutes. These rapid effects can be mediated by ESRs or the G protein-coupled estrogen receptor GPER, also known as GPR30. The effects of estrogen on cell proliferation, differentiation and apoptosis are often mediated by growth factors. The understanding of the cross-talk between androgen, estrogen and growth factors signaling pathways is therefore essential to understand the physiopathological mechanisms of estrogen action. In this review we focused on recent discoveries about the nature of the estrogen receptors, and on the signaling and function of estrogen in the male reproductive system.

Integrative depiction of the male reproductive system of the commercial purple crab Homalaspis plana (Platyxanthidae): Structure and function

2019 ◽  
Vol 280 (11) ◽  
pp. 1693-1705
Author(s):  
Luis M. Pardo ◽  
Fernando J. Zara ◽  
Marcela P. Riveros ◽  
Kurt Paschke ◽  
Katrin Pretterebner ◽  
...  
Keyword(s):  
Reproductive System ◽  
Structure And Function ◽  
Male Reproductive System ◽  
And Function

scholarly journals Alterations in egg white-related genes expression in response to hormonal stimulation

Reproduction ◽  
2020 ◽  
Vol 160 (5) ◽  
pp. 793-801
Author(s):  
Minkyeong Lee ◽  
Changwon Yang ◽  
Gwonhwa Song ◽  
Whasun Lim
Keyword(s):  
Reproductive System ◽  
Hormonal Regulation ◽  
Egg Production ◽  
Reproductive Tract ◽  
Egg White ◽  
Female Reproductive Tract ◽  
Expression Of Genes ◽  
Egg White Proteins ◽  
Study Results ◽  
Genes Encoding

The reproductive tract in avian females is sensitive to hormonal regulation. Exogenous estrogen induces immature oviduct development to improve egg production after molting. In this process, regressed female reproductive tract is regenerated in response to the secretion of estrogen. However, there is limited knowledge on the physiological mechanisms underlying the regulation of the avian female reproductive system. In our previous study, results from microarray analysis revealed that the expression of genes encoding egg white proteins is affected during molting. Herein, we artificially induced the molting period in chickens through a zinc-containing diet. Subsequently, changes in the expression of genes encoding egg white proteins were confirmed in the oviduct tissue. The levels of MUC5B, ORM1, RTBDN, and TENP mRNA were significantly high in the oviduct, and the genes were repressed in the regression phase, whereas these were expressed in the recrudescence phase, particularly in the luminal epithelium and glandular epithelium of the oviduct, during molting. Moreover, we observed that gene expression was induced in the magnum, the site for the secretion of egg white components. Next, differences in expression levels of the four genes in normal and cancerous ovaries were compared. Collectively, results suggest that the four selected genes are expressed in the female chicken reproductive tract in response to hormonal regulation, and egg white protein-encoding genes may serve as modulators of the reproductive system in hens.

Diversity of reproductive behaviour in platyhelminth parasites: insemination in some benedeniine (capsalid) monogeneans

Parasitology ◽  
1992 ◽  
Vol 104 (3) ◽  
pp. 489-496 ◽  
Author(s):  
G. C. Kearn ◽  
I. D. Whittington
Keyword(s):  
Reproductive System ◽  
Reproductive Tract ◽  
Reproductive Behaviour ◽  
Copulatory Organ ◽  
Female Reproductive Tract ◽  
Male Reproductive System ◽  
First Time

Considerable diversity has been found in the reproductive behaviour of benedeniine (capsalid) monogenean parasites. Mating has been observed in Benedenia sp. 1 from the gills of Lutjanus carponatatus; externally attached spermatophores are not involved and parasites indulge in mutual cross-insemination with intromission. In contrast, there is evidence of spermatophore involvement in Benedenia sp. 2 from the fins of Lethrinus miniatus; mating was not observed but an individual was found carrying an external ovoid spermatophore attached by a stalk lodged in the vagina. In specimens of Benedeniella macrocolpa and B. posterocolpa, in which the male reproductive system was functional and the female system not fully developed, the everted cirrus was seen to be lodged in the parasite's own uterus, with, in some individuals, the tip of the cirrus inside the ootype. This is the first time that the copulatory organ has been observed inside the female reproductive tract of the same individual, not just in benedeniines but in monogeneans in general, and is also the first demonstration that monogeneans are capable of self-insemination via the uterine route.

scholarly journals Chlamydia pecorum Infection in the Male Reproductive System of Koalas (Phascolarctos cinereus)

2018 ◽  
Vol 56 (2) ◽  
pp. 300-306 ◽  
Author(s):  
Chiara Palmieri ◽  
Lyndal Hulse ◽  
Sara Pagliarani ◽  
Rebecca Larkin ◽  
Damien P. Higgins ◽  
...  
Keyword(s):  
Reproductive System ◽  
Reproductive Tract ◽  
Male Reproductive System ◽  
Chlamydia Infection ◽  
Male Reproductive Tract ◽  
Tissue Samples ◽  
Phascolarctos Cinereus ◽  
Membranous Urethra ◽  
Chlamydia Pecorum ◽  
Serious Disease

Chlamydiosis is the most documented and serious disease of koalas, characterized by ocular, urinary, and reproductive lesions. Since little attention has been paid to the pathological effects of this infection in the male reproductive system, we aimed to determine the incidence and severity of reproductive pathology associated with chlamydial infection in male koalas submitted to koala hospitals in southeast Queensland. The entire reproductive tract from 62 sexually mature male koalas not suitable for rehabilitation was evaluated and 677 tissue samples were collected for histology, immunohistochemistry (IHC), and real-time polymerase chain reaction (qPCR). Lymphoplasmacytic inflammation was observed in 178 of 677 (26.3%) tissue samples from the upper and lower reproductive tract, mainly in the prostatic, penile, and membranous urethra. IHC was positive for the chlamydial antigen in 19 of 451 normal samples (4.2%) and 46 of 178 samples with inflammation (25.8%), located within the cytoplasm of epithelial cells of the epididymis, vas deferens, prostate, bulbourethral glands, and the prostatic membranous and penile urethra. Chlamydia pecorum was detected via qPCR in 319 of 451 normal samples (70.7%) and 159 of 178 samples with inflammation (89.3%), with the highest incidence in the penile urethra, prostate, membranous urethra, and bulbourethral glands. This study suggests that Chlamydia infection in the male reproductive tract is more widespread than originally thought. Furthermore, the male reproductive tract might be a reservoir for persistent chlamydial infections in koalas, with important implications for prophylactic strategies and epidemiology.

scholarly journals Necroptosis promotes the Aging of the Male Reproductive System in Mice

2017 ◽  
Author(s):  
Dianrong Li ◽  
Lingjun Meng ◽  
Tao Xu ◽  
Yaning Su ◽  
Xiao Liu ◽  
...  
Keyword(s):  
Reproductive System ◽  
Accelerated Aging ◽  
Reproductive Organs ◽  
Male Reproductive System ◽  
Necrotic Cell Death ◽  
Wild Type ◽  
Necrotic Cell ◽  
Age Related ◽  
And Function ◽  
Age Related Changes

AbstractNecroptosis is a form of programmed necrotic cell death in mammals that is mediated by a pair of kinases, RIP1 and RIP3, as well as the RIP3 substrate MLKL. We report here that male reproductive organs of both RIP3-and MLKL-knockout mice retain “youthful” morphology and function into advanced age, while those of age-matched wild type mice deteriorate. The RIP3 phosphorylation of MLKL, the activation marker of necroptosis, is detected in spermatogonial stem cells in the testes of old but not in young wild type mice. When the testes of young wild type mice are given a local necroptotic stimulus, their reproductive organs showed accelerated aging. Feeding of wild type mice with an RIP1 inhibitor prior to the normal onset of age-related changes in their reproductive organs blocked the appearance of signs of aging. Thus, necroptosis in testes promotes the aging-associated deterioration of the male reproductive system in mice.

scholarly journals RIPK1-RIPK3-MLKL-dependent necrosis promotes the aging of mouse male reproductive system

eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Dianrong Li ◽  
Lingjun Meng ◽  
Tao Xu ◽  
Yaning Su ◽  
Xiao Liu ◽  
...  
Keyword(s):  
Reproductive System ◽  
Accelerated Aging ◽  
Reproductive Organs ◽  
Male Reproductive System ◽  
Necrotic Cell Death ◽  
Wild Type ◽  
Necrotic Cell ◽  
Age Related ◽  
And Function ◽  
Age Related Changes

A pair of kinases, RIPK1 and RIPK3, as well as the RIPK3 substrate MLKL cause a form of programmed necrotic cell death in mammals termed necroptosis. We report here that male reproductive organs of both Ripk3- and Mlkl-knockout mice retain ‘youthful’ morphology and function into advanced age, while those of age-matched wild-type mice deteriorate. The RIPK3 phosphorylation of MLKL, the activation marker of necroptosis, is detected in spermatogonial stem cells in the testes of old but not in young wild-type mice. When the testes of young wild-type mice are given a local necroptotic stimulus, their reproductive organs showed accelerated aging. Feeding of wild-type mice with an RIPK1 inhibitor prior to the normal onset of age-related changes in their reproductive organs blocked the appearance of signs of aging. Thus, necroptosis in testes promotes the aging-associated deterioration of the male reproductive system in mice.

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