Experimental Data on the Function of the Interstitium of the Gonads: Experiments with Cockerels

1947 ◽  
Vol s3-88 (2) ◽  
pp. 135-150
Author(s):  
J. W. SLUITER ◽  
G. J. VAN OORDT
Keyword(s):  
Experimental Data ◽  
Connective Tissue ◽  
Leydig Cells ◽  
Cell Types ◽  
Sex Hormone ◽  
Secretory Cells ◽  
Secretory Function ◽  
Glandular Cells ◽  
Male Sex ◽  
Secondary Function

1. The relative volumes of the testes and their components of 31 cockerels, 2-200 days old, were calculated and compared with the size of their increasing head appendages (Text-figs. 1a-d, 2); in addition, the effect of gestyl-administration on testes of cockerels of this age was investigated. 2. Several types of interstitial testis-cells could be distinguished morphologically and physiologically (Text-figs. 3-6 and Pl. 1); these cell-types were studied with different techniques and counted separately. 3. The main types of the interstitial cells are: (a) Lipoid cells, totally packed with lipoid globules. These cells, which are considered by many authors as fully developed Leydig cells, are not directly connected with the production of the male sex hormone; perhaps they have a secondary function in this respect, as cholesterolderivatives are stored in these cells (Pl. 1, Text-fig. 3a). (b) Secretory cells, characterized by the absence of lipoid vacuoles and the presence of numerous granular and filamentous mitochondria. These secretory cells, which produce the male sex hormone, can be divided into secretory cells A (Text-fig. 6a) without, and secretory cells B with, one large vacuole (Text-figs. 6b, 6c, 6d). 4. A considerable and partly intercellular storage of lipoids may take place at any age in the intertubular connective tissue (Text-figs. 3-4 and Pl. 1). 5. The number of the lipoid cells depends on the nutritive conditions of the animal and the development of its testes (Text-fig. 7). 6. In older cockerels most of the glandular cells lose their secretory function and pass over into lipoid storing cells. 7. Therefore we agree with Benoit, when he denies the occurrence of a ‘secretion de luxe’, but we cannot accept the presence of a ‘parenchyme de luxe’ in the testes of older cockerels.

Effect of nutrition on the onset of male sex hormone activity and sperm formation in monozygous bull-calves

1957 ◽  
Vol 147 (928) ◽  
pp. 332-351 ◽  
Keyword(s):  
Citric Acid ◽  
Food Intake ◽  
Seminal Vesicles ◽  
Sex Hormone ◽  
Seminiferous Tubules ◽  
Interstitial Tissue ◽  
Secretory Function ◽  
Histological Changes ◽  
Bull Calves ◽  
Male Sex

The effect of a reduced food intake on the onset of androgenic activity and the appearance of spermatozoa was studied in maturing bull-calves. Three pairs of identical twin-calves were used. In each instance, one twin was reared on a ‘high plane’ of nutrition, consisting of normal feeding, and the other on a ‘low plane’ of reduced food intake. Semen was collected from the twin-calves by the electric stimulation method, and analyzed for sperm density, fructose and citric acid. The appearance of fructose and citric acid in semen was taken as an indicator of the onset of secretory function in the seminal vesicles, which depends on the presence of the male sex hormone. Fructose and citric acid appeared in electrically-discharged semen from the normally fed bull-calves several months before the first spermatozoa. This suggested that the male sex hormone began to act in the young animal several months before the appearance of the first spermatozoa. Restriction of food intake had a marked delaying influence on the onset of fructose and citric acid secretion, and a smaller delaying effect on the appearance of spermatozoa. The delaying effect of underfeeding on the secretory function of the bull seminal vesicles as reflected in the diminished output of fructose and citric acid, appeared to be the result of an inadequate stimulation of the gonads by the gonadotrophic hormone. Injections of gonadotrophin were found to elicit a prompt appearance of both fructose and citric acid in the semen. Alterations in the composition of semen caused by underfeeding were shown to run parallel to histological changes in the testes and male accessory organs. Low-plane feeding retarded the differentiation of the seminiferous tubules and of the interstitial tissue in the male gonads. The histological changes in the seminal vesicles induced by underfeeding corresponded closely to the diminished secretory output of fructose and citric acid in these glands.

The structure of the gills of the axolotl, Ambystoma mexicanum

1987 ◽  
Vol 45 ◽  
pp. 824-825
Author(s):  
Mohinder S. Jarial
Keyword(s):  
Leydig Cells ◽  
Secretory Granules ◽  
Light And Electron Microscopy ◽  
Cell Types ◽  
Ambystoma Mexicanum ◽  
Basal Cells ◽  
Granular Cells ◽  
Gill Filaments ◽  
Mitotic Figures ◽  
Apical Membranes

The axolotl is a strictly aquatic salamander in which the larval external gills are retained throughout life. The external gills of the adult axolotl have been studied by light and electron microscopy for ultrastructural evidence of ionic transport. The thin epidermis of the gill filaments and gill stems is composed of 3 cell types: granular cells, the basal cells and a sparce population of intervening Leydig cells. The gill epidermis is devoid of muscles, and no mitotic figures were observed in any of its cells.The granular cells cover the gill surface as a continuous layer (Fig. 1, G) and contain secretory granules of different forms, located apically (Figs.1, 2, SG). Some granules are found intimately associated with the apical membrane while others fuse with it and release their contents onto the external surface (Fig. 3). The apical membranes of the granular cells exhibit microvilli which are covered by a PAS+ fuzzy coat, termed “glycocalyx” (Fig. 2, MV).

Correlative transmission and high-resolution scanning electron microscopic studies on pituitary cells

1990 ◽  
Vol 48 (3) ◽  
pp. 20-21
Author(s):  
S. Tai
Keyword(s):  
Cell Types ◽  
Depth Of Field ◽  
Secretory Cells ◽  
Specific Cell ◽  
Pituitary Cells ◽  
Electron Microscopic ◽  
3 Dimensional ◽  
Microscopic Studies ◽  
Structure And Activity ◽  
Intracellular Structure

Extensive cytological and histological research, correlated with physiological experimental analysis, have been done on the anterior pituitaries of many different vertebrates which have provided the knowledge to create the concept that specific cell types synthesize, store and release their specific hormones. These hormones are stored in or associated with granules. Nevertheless, there are still many doubts - that need further studies, specially on the ultrastructure and physiology of these endocrine cells during the process of synthesis, transport and secretion, whereas some new methods may provide the information about the intracellular structure and activity in detail.In the present work, ultrastructural study of the hormone-secretory cells of chicken pituitaries have been done by using TEM as well as HR-SEM, to correlate the informations obtained from 2-dimensional TEM micrography with the 3-dimensional SEM topographic images, which have a continous surface with larger depth of field that - offers the adventage to interpretate some intracellular structures which were not possible to see using TEM.

scholarly journals Anaphylactic Degranulation of Mast Cells: Focus on Compound Exocytosis

2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Ofir Klein ◽  
Ronit Sagi-Eisenberg
Keyword(s):  
Mast Cell ◽  
Mast Cells ◽  
Molecular Mechanisms ◽  
Secretory Granules ◽  
Cell Types ◽  
Secretory Cells ◽  
Regulated Exocytosis ◽  
Open Questions ◽  
Conflicting Evidence ◽  
Compound Exocytosis

Anaphylaxis is a notorious type 2 immune response which may result in a systemic response and lead to death. A precondition for the unfolding of the anaphylactic shock is the secretion of inflammatory mediators from mast cells in response to an allergen, mostly through activation of the cells via the IgE-dependent pathway. While mast cells are specialized secretory cells that can secrete through a variety of exocytic modes, the most predominant mode exerted by the mast cell during anaphylaxis is compound exocytosis—a specialized form of regulated exocytosis where secretory granules fuse to one another. Here, we review the modes of regulated exocytosis in the mast cell and focus on compound exocytosis. We review historical landmarks in the research of compound exocytosis in mast cells and the methods available for investigating compound exocytosis. We also review the molecular mechanisms reported to underlie compound exocytosis in mast cells and expand further with reviewing key findings from other cell types. Finally, we discuss the possible reasons for the mast cell to utilize compound exocytosis during anaphylaxis, the conflicting evidence in different mast cell models, and the open questions in the field which remain to be answered.

scholarly journals Signaling Control of Mucociliary Epithelia: Stem Cells, Cell Fates, and the Plasticity of Cell Identity in Development and Disease

2021 ◽  
pp. 1-18
Author(s):  
Peter Walentek
Keyword(s):  
Stem Cells ◽  
Mucociliary Clearance ◽  
Cell Types ◽  
Secretory Cells ◽  
Chronic Obstructive ◽  
Cell Identity ◽  
Obstructive Pulmonary Disease ◽  
Congenital Diseases ◽  
Inhaled Particles ◽  
Mucociliary Epithelia

Mucociliary epithelia are composed of multiciliated, secretory, and stem cells and line various organs in vertebrates such as the respiratory tract. By means of mucociliary clearance, those epithelia provide a first line of defense against inhaled particles and pathogens. Mucociliary clearance relies on the correct composition of cell types, that is, the proper balance of ciliated and secretory cells. A failure to generate and to maintain correct cell type composition and function results in impaired clearance and high risk to infections, such as in congenital diseases (e.g., ciliopathies) as well as in acquired diseases, including asthma, chronic obstructive pulmonary disease (COPD), and idiopathic pulmonary fibrosis (IPF). While it remains incompletely resolved how precisely cell types are specified and maintained in development and disease, many studies have revealed important mechanisms regarding the signaling control in mucociliary cell types in various species. Those studies not only provided insights into the signaling contribution to organ development and regeneration but also highlighted the remarkable plasticity of cell identity encountered in mucociliary maintenance, including frequent trans-differentiation events during homeostasis and specifically in disease. This review will summarize major findings and provide perspectives regarding the future of mucociliary research and the treatment of chronic airway diseases associated with tissue remodeling.

scholarly journals Regulatory Role of Sex Hormones in Cardiovascular Calcification

2021 ◽  
Vol 22 (9) ◽  
pp. 4620
Author(s):  
Holly J. Woodward ◽  
Dongxing Zhu ◽  
Patrick W. F. Hadoke ◽  
Victoria E. MacRae
Keyword(s):  
Cardiovascular Disease ◽  
Sex Differences ◽  
Sexual Dimorphism ◽  
Aortic Stenosis ◽  
Sex Hormones ◽  
Sex Hormone ◽  
Increased Risk ◽  
Male Sex ◽  
Primary Male

Sex differences in cardiovascular disease (CVD), including aortic stenosis, atherosclerosis and cardiovascular calcification, are well documented. High levels of testosterone, the primary male sex hormone, are associated with increased risk of cardiovascular calcification, whilst estrogen, the primary female sex hormone, is considered cardioprotective. Current understanding of sexual dimorphism in cardiovascular calcification is still very limited. This review assesses the evidence that the actions of sex hormones influence the development of cardiovascular calcification. We address the current question of whether sex hormones could play a role in the sexual dimorphism seen in cardiovascular calcification, by discussing potential mechanisms of actions of sex hormones and evidence in pre-clinical research. More advanced investigations and understanding of sex hormones in calcification could provide a better translational outcome for those suffering with cardiovascular calcification.

Ultrastructure of scent glands in larvae of Apateticus bracteatus (Hemiptera: Pentatomidae) and chemical composition of the secretion

1980 ◽  
Vol 58 (11) ◽  
pp. 2105-2115 ◽  
Author(s):  
Jean Percy ◽  
J. A. MacDonald ◽  
J. Weatherston
Keyword(s):  
Chemical Composition ◽  
Interstitial Cells ◽  
Secretory Cells ◽  
Scent Glands ◽  
Volatile Constituents ◽  
Dorsal Wall ◽  
Anterior Dorsal ◽  
Glandular Cells ◽  
Gland Function ◽  
Dorsal Abdominal Glands

The three dorsal abdominal glands in larvae of Apateticus bracteatus (Pentatomidae) secrete a mixture of compounds. Major volatile constituents of the secretion are identified, herein, as tridecane and 2-octenal. There are also trace amounts of 2-hexenal and two other unidentified compounds.Each of the glands has paired orifices that are located between tergites 3/4, 4/5, and 5/6, but only the most anterior gland is paired. In anterior glands of midinstar larvae, glandular cells associated with ducts, and interstitial glandular cells are distributed along the ventral walls of the reservoirs. In posterior glands, columnar glandular cells are located in the anterior dorsal wall of the reservoirs; secretory cells associated with ducts, and nonglandular interstitial cells are distributed throughout the ventral and posterior walls of the reservoirs. The interstitial glandular cells of the anterior gland and the columnar glandular cells of the middle and posterior glands contain cytoplasmic organelles characteristic of lipid-producing cells. In all glands the secretory cells associated with ducts secrete lipids. Evidence indicating the importance of Golgi and ER in secretion synthesis is presented. The reservoirs and ducts have a thin cuticular lining.The bearing of the results on present ideas of gland function in Heteroptera is discussed.

Ultrastructure of the female reproductive organs (ovary, vitellaria, and Mehlis' gland) of Halipegus eccentricus (Trematoda: Derogenidae)

1986 ◽  
Vol 64 (10) ◽  
pp. 2203-2212 ◽  
Author(s):  
Jon M. Holy ◽  
Darwin D. Wittrock
Keyword(s):  
Cell Types ◽  
Reproductive Organs ◽  
Golgi Body ◽  
Digenetic Trematode ◽  
Secretory Cells ◽  
Cortical Granules ◽  
Golgi Bodies ◽  
Transmission Electron ◽  
Vitelline Cells ◽  
Female Reproductive Organs

The female reproductive organs (ovary, vitellaria, and Mehlis' gland) of the digenetic trematode Halipegus eccentricus were studied by transmission electron microscopy. Oocytes entered diplotene while in the ovary and produced cortical granules and lipid bodies. Vitelline cells produced large amounts of eggshell protein but no yolk bodies. Two types of Mehlis' gland secretory cells were present, distinguishable by the morphology of their rough endoplasmic reticulum, Golgi bodies, and secretory bodies, and by the persistence of recognizable secretory material within the ootype lumen after exocytosis. In an attempt to standardize the nomenclature regarding the cell types of the Mehlis' gland, a classification that takes into account these four criteria is proposed. Two basic types of Golgi body organization were noted for the cells of the female reproductive system: a stack of flattened cisternae (Mehlis' gland alpha cells) and spherical Golgi bodies with vesicular cisternae (oocytes, vitelline cells, and Mehlis' gland beta cells).

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