Homologs of Leydig and Sertoli Cells in the Testis of the Teleost, Oryzias Latipes

Author(s):  
Edward W. Gresik

The testis of O. latipes is composed of cysts containing germinal elements Tn various stages of spermatogenesis (Fig. 1). The simple epithelial cells of the cyst wall are the Sertoli cell (SC) homologs. When the contained germinal elements have matured, the cyst epithelium fuses with that of the terminal divisions of the efferent duct system. In the connective tissue stroma surrounding the cysts and ducts, the Leydig cell (LC) homologs are found.The LC (Fig. 2) contains a central vesicular nucleus with a distinct nucleolus. Flattened cisternae of rough ER are distributed throughout the cytoplasm; smooth ER, usual in steroidogenic cells, is not present.

1994 ◽  
Vol 71 (05) ◽  
pp. 684-691 ◽  
Author(s):  
László Damjanovich ◽  
Csaba Turzó ◽  
Róza Ádány

SummaryThe plasminogen activation system is a delicately balanced assembly of enzymes which seems to have primary influence on tumour progression. The conversion of plasminogen into serine protease plasmin with fibrinolytic activity depends on the actual balance between plasminogen activators (urokinase type; u-PA and tissue type; t-PA) and their inhibitors (type 1 and 2 plasminogen activator inhibitors; PAI-1 and PAI-2). The purpose of this study was to determine the exact histological localization of all the major factors involved in plasminogen activation, and activation inhibition (plasmin system) in benign and malignant breast tumour samples. Our results show that factors of the plasmin system are present both in benign and malignant tumours. Cancer cells strongly labelled for both u-PA and t-PA, but epithelial cells of fibroadenoma samples were also stained for plasminogen activators at least as intensively as tumour cells in cancerous tissues. In fibroadenomas, all the epithelial cells were labelled for PAM. Staining became sporadic in malignant tumours, cells located at the periphery of tumour cell clusters regularly did not show reaction for PAI-1. In the benign tumour samples the perialveolar connective tissue stroma contained a lot of PAI-1 positive cells, showing characteristics of fibroblasts; but their number was strongly decreased in the stroma of malignant tumours. These findings indicate that the higher level of u-PA antigen, detected in malignant breast tumour samples by biochemical techniques, does not necessarily indicate increased u-PA production by tumour cells but it might be owing to the increased number of cells producing u-PA as well. In malignant tumours PAI-1 seems to be decreased in the frontage of malignant cell invasion; i.e. malignant cells at the host/tumour interface do not express PAI-1 in morphologically detectable quantity and in the peritumoural connective tissue the number of fibroblasts containing PAI-1 is also decreased.


2021 ◽  
pp. 1-14
Author(s):  
Yuanyuan Li ◽  
Jinbo Li ◽  
Man Cai ◽  
Zhanfen Qin

The knowledge of testis development in amphibians relative to amniotes remains limited. Here, we used Xenopus laevis to investigate the process of testis cord development. Morphological observations revealed the presence of segmental gonomeres consisting of medullary knots in male gonads at stages 52–53, with no distinct gonomeres in female gonads. Further observations showed that cell proliferation occurs at specific sites along the anterior-posterior axis of the future testis at stage 50, which contributes to the formation of medullary knots. At stage 53, adjacent gonomeres become close to each other, resulting in fusion; then (pre-)Sertoli cells aggregate and form primitive testis cords, which ultimately become testis cords when germ cells are present inside. The process of testis cord formation in X. laevis appears to be more complex than in amniotes. Strikingly, steroidogenic cells appear earlier than (pre-)Sertoli cells in differentiating testes of X. laevis, which differs from earlier differentiation of (pre-)Sertoli cells in amniotes. Importantly, we found that the mesonephros is connected to the testis gonomere at a specific site at early larval stages and that these connections become efferent ducts after metamorphosis, which challenges the previous concept that the mesonephric side and the gonadal side initially develop in isolation and then connect to each other in amphibians and amniotes.


1968 ◽  
Vol 51 (6) ◽  
pp. 770-784 ◽  
Author(s):  
J. T. Gatzy ◽  
W. O. Berndt

Epithelial cells of the toad bladder were disaggregated with EDTA, trypsin, hyaluronidase, or collagenase and were then scraped free of the underlying connective tissue. In most experiments EDTA was complexed with a divalent cation before the tissue was scraped. QOO2, sucrose and inulin spaces, and electrolytes of the isolated cells were measured. Cells disaggregated by collagenase or hyaluronidase consumed O2 at a rate of 4 µl hr-1 dry wt-1. QOO2 was increased 50% by ADH (100 U/liter) or by cyclic 3',5'-AMP (10 mM/liter). Na+-free Ringer's depressed the QOO2 by 40%. The QOO2 of cells prepared by trypsin treatment or by two EDTA methods was depressed by Na+-free Ringer's but was stimulated relatively little by ADH. Two other EDTA protocols produced cells that did not respond to Na+ lack or ADH. The intracellular Na+ and K+ concentrations of collagenase-disaggregated cells were 32 and 117 mEq/kg cell H2O, respectively. Cation concentrations of hyaluronidase cells were similar, but cells that did not respond to ADH had higher intracellular Na+ concentrations. Cells unresponsive to ADH and Na+ lack had high sucrose spaces and low transcellular membrane gradients of Na+, K+, and Cl-. The results suggest that trypsin and EDTA disaggregation damage the active Na+ transport system of the isolated cell. Certain EDTA techniques may also produce a general increase in permeability. Collagenase and hyaluronidase cells appear to function normally.


1988 ◽  
Vol 89 (2) ◽  
pp. 175-188
Author(s):  
H. Ueda ◽  
L.L. Tres ◽  
A.L. Kierszenbaum

A cocultivation chamber and two types of permeable substrates have been used to study: (1) the culture patterns of rat Sertoli and peritubular cells, and Sertoli cells cocultured with spermatogenic cells or peritubular cells; and (2) the polarized secretion of Sertoli cell-specific proteins transferrin, S70 and S45-S35 heterodimeric protein. Substrates included a nylon mesh (with openings of 100 micron) coated with extracellular matrix (ECM) material and an uncoated microporous filter (with pores of 0.45 micron). Sertoli cells cultured on ECM-coated nylon mesh organized a continuous sheet of multilayered epithelial cells essentially devoid of spermatogenic cells while peritubular cells formed a layer of squamous cells. Sertoli cells cultured on uncoated microporous substrate formed a continuous sheet of cuboidal epithelial cells with numerous basal cytoplasmic processes projecting into the substrate and abundant apically located spermatogenic cells, while peritubular cells organized one or two layers of loose squamous cells. [35S]methionine-labelled secretory proteins resolved by two-dimensional polyacrylamide gel electrophoresis and autoradiography displayed cell-specific patterns that were slightly influenced by the type of substrate. Sertoli cells cocultured with peritubular cells on uncoated microporous substrate under conditions that enabled separation of apical and basal surfaces, secreted proteins in a polarized fashion. While transferrin was released bidirectionally, S45-S35 heterodimeric protein was released apically. S70 was detected in both apical and basal compartments. We conclude from these studies that: (1) the number of spermatogenic cells decreases when Sertoli-spermatogenic cell cocultures are prepared on ECM-coated nylon substrate; and (2) Sertoli cells in coculture with spermatogenic or peritubular cells on uncoated microporous substrate, organize continuous sheets displaying polarized protein secretion.


Reproduction ◽  
2003 ◽  
pp. 879-887 ◽  
Author(s):  
E Anton

The apoptotic process evoked by efferent duct ligation in the testes of adult rats was followed for 10 days by differential staining for haematoxylin-eosin, periodic acid-Schiff and a modified trichrome technique in optical microscopy and by ultrastructural localization of acid phosphatase. Round spermatids showed the first effects of efferent duct ligation. At day 3 after ligation, annular clumps of chromatin with typical apoptotic characteristics appeared against the nuclear membrane of these cells. Afterwards, membranous structures and a wide separation between the two layers of the nuclear membrane were observed but nuclear fragmentation did not occur and apoptotic granules were not seen. Cytoplasmic components were also altered, and severely damaged organoids and empty vacuoles lacking acid phosphatase reaction were frequently seen. On day 2 after efferent duct ligation, multinucleated giant cells appeared, which displayed similar characteristics as spermatids and showed no acid phosphatase reaction. Although abnormal spermatids and multinucleated giant cells were surrounded by the cytoplasm of Sertoli cells, neither lysosomal acid phosphatase nor phagocytic activity was detected. It is concluded that efferent duct ligation specifically affects round immature spermatids eliciting a partial nuclear apoptotic response that is not accompanied by autophagic or heterophagic activity and without lysosomal participation in Sertoli cells.


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