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 ◽  
...  
Endocrinology ◽  
2008 ◽  
Vol 149 (8) ◽  
pp. 4209-4217 ◽  
Author(s):  
Brenda Anguiano ◽  
Nuri Aranda ◽  
Guadalupe Delgado ◽  
Carmen Aceves

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.


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 ◽  
...  

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.


Author(s):  
D. A. Parry

Spadella cephaloptera1. The oesophageal epithelium is composed of granular and vacuolated cells. The former produce a glutinous secretion which appears to immobilize and lubricate the prey. The function of the vacuolated cells remains undetermined.2. The intestinal epithelium is composed of gland cells and absorptive cells. The gland cells contain large vacuoles which disrupt when food is taken, restitution taking several hours. The absorptive cells accumulate large concretions of fat and other material as digestion proceeds; later this gradually disappears.3. The absorptive cells in the intestine are ciliated. The cilia may be concerned with respiration and excretion; there is no evidence that they are concerned with osmoregulation.4. The rectum has a ciliated columnar epithelium.5. The general course of feeding and digestion,is discussed.6. It is stated in a footnote that the reproductive system of Spadella is similar to that of Sagitta.Sagitta setosa7. The oesophagus is divided histologically as follows: (i) a region of granular cells round the mouth; (ii) a region of vacuolated cells; (iii) a region of compound granular cells; (iv) a second region of granular cells. The granular cells produce a profuse secretion with probably the same function as the glutinous secretion in Spadella.8. The intestinal epithelium is composed of compound granular cells and simple columnar cells. By comparison with the intestine of Spadella the former are regarded as enzyme-secreting cells and the latter as absorptive.


Author(s):  
Sijia Yao ◽  
Jorge Lopez-Tello ◽  
Amanda N Sferruzzi-Perri

Abstract Exposures to adverse conditions in utero can lead to permanent changes in the structure and function of key physiological systems in the developing fetus, increasing the risk of disease and premature aging in later postnatal life. When considering the systems that could be affected by an adverse gestational environment, the reproductive system of developing female offspring may be particularly important, as changes have the potential to alter both reproductive capacity of the first generation, as well as health of the second generation through changes in the oocyte. The aim of this review is to examine the impact of different adverse intrauterine conditions on the reproductive system of the female offspring. It focuses on the effects of exposure to maternal undernutrition, overnutrition/obesity, hypoxia, smoking, steroid excess, endocrine disrupting chemicals and pollutants during gestation and draws on data from human and animal studies to illuminate underlying mechanisms. The available data indeed indicate that adverse gestational environments alter the reproductive physiology of female offspring with consequences for future reproductive capacity. These alterations are mediated via programmed changes in the hypothalamic–pituitary gonadal axis and the structure and function of reproductive tissues, particularly the ovaries. Reproductive programming may be observed as a change in the timing of puberty onset and menopause/reproductive decline, altered menstrual/estrous cycles, polycystic ovaries and elevated risk of reproductive tissue cancers. These reproductive outcomes can affect the fertility and fecundity of the female offspring, however, further work is needed to better define the possible impact of these programmed changes on subsequent generations.


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