scholarly journals Immunocytochemistry of the pituitary glycoprotein hormones.

1976 ◽  
Vol 24 (7) ◽  
pp. 846-863 ◽  
Author(s):  
G C Moriarty
Keyword(s):  
Secretory Granules ◽  
Thyroid Stimulating Hormone ◽  
Type I ◽  
Glycoprotein Hormones ◽  
Type Ii ◽  
Electron Microscopic ◽  
Tsh Cells ◽  
Immunocytochemical Techniques ◽  
Lh Cells ◽  
Stimulating Hormone

The storage sites of the pituitary glycoprotein hormones were identified with the use of electron microscopic immunocytochemical techniques and antisera to the beta (beta) chains of follicle-stimulating hormone (FSH), luteinizing hormone (LH) and thyroid-stimulating hormone (TSH). The TSH cells in normal rats is ovoid or angular and contains small granules 60-160 nm in diameter. In TSH cells hypertrophied 45 days after thyroidectomy, staining is in globular patches in granules or diffusely distributed in the expanded profiles of dilated rough endoplasmic reticulum. The gonadotrophs (FSH and LH cells) exhibited three different morphologies. Type I cells are ovoid with a population of large granules and a population of small granules. Staining for FSHbeta or LHbeta was intense and specific only in the large granules (diameter of 400 nm or greater). Type II cells are angular or stellate and contain numerous secretory granules averaging 200-220 nm in diameter. They predominate during stages in the estrous cycle when FSH or LH secretion is high. Type III cells look like adrenocorticotropin (ACTH) cells in that they are stellate with peripherally arranged granules. They generally stain only with anti-FSHbeta and their staining can not be abolished by the addition of 100 ng ACTH. In preliminary quantitative studies of cycling females, we found that on serial sections FSH cells and LH cells show similar shifts to a more angular population of cells during stages of active secretion. However, the shifts are not in phase with one another. Furthermore, there are at least 1.5 times more FSH cells than LH cells at all stages of the cycle. Our collection of serial cells shows that some cells (usually type I or II) stain for both gonadotropic hormones, whereas others (usually type II or III) contain only one.

scholarly journals A vital region for human glycoprotein hormone trafficking revealed by an LHB mutation

2016 ◽  
Vol 231 (3) ◽  
pp. 197-207 ◽  
Author(s):  
Iulia Potorac ◽  
Adolfo Rivero-Müller ◽  
Ashutosh Trehan ◽  
Michał Kiełbus ◽  
Krzysztof Jozwiak ◽  
...  
Keyword(s):  
Luteinizing Hormone ◽  
Pubertal Development ◽  
Gene Mutations ◽  
Thyroid Stimulating Hormone ◽  
Beta Subunits ◽  
Glycoprotein Hormones ◽  
Glycoprotein Hormone ◽  
Pubertal Delay ◽  
The Common ◽  
Stimulating Hormone

Glycoprotein hormones are complex hormonally active macromolecules. Luteinizing hormone (LH) is essential for the postnatal development and maturation of the male gonad. Inactivating Luteinizing hormone beta (LHB) gene mutations are exceptionally rare and lead to hypogonadism that is particularly severe in males. We describe a family with selective LH deficiency and hypogonadism in two brothers. DNA sequencing of LHB was performed and the effects of genetic variants on hormone function and secretion were characterized by mutagenesis studies, confocal microscopy and functional assays. A 20-year-old male from a consanguineous family had pubertal delay, hypogonadism and undetectable LH. A homozygous c.118_120del (p.Lys40del) mutation was identified in the patient and his brother, who subsequently had the same phenotype. Treatment with hCG led to pubertal development, increased circulating testosterone and spermatogenesis. Experiments in HeLa cells revealed that the mutant LH is retained intracellularly and showed diffuse cytoplasmic distribution. The mutated LHB heterodimerizes with the common alpha-subunit and can activate its receptor. Deletion of flanking glutamic acid residues at positions 39 and 41 impair LH to a similar extent as deletion of Lys40. This region is functionally important across all heterodimeric glycoprotein hormones, because deletion of the corresponding residues in hCG, follicle-stimulating hormone and thyroid-stimulating hormone beta-subunits also led to intracellular hormone retention. This novel LHB mutation results in hypogonadism due to intracellular sequestration of the hormone and reveals a discrete region in the protein that is crucial for normal secretion of all human glycoprotein hormones.

scholarly journals OBSERVATIONS ON ETCHED ENAMEL IN NON-ERUPTED DECIDUOUS MOLARS: A SCANNING ELECTRON MICROSCOPIC STUDY

1997 ◽  
Vol 11 (3) ◽  
pp. 157-160 ◽  
Author(s):  
Marcelo FAVA ◽  
Ii-Sei WATANABE ◽  
Flávio FAVA DE MORAES ◽  
Luciane RIBEIRO DE REZENDE SUCASAS DA COSTA
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Phosphoric Acid ◽  
Acid Etching ◽  
Etching Time ◽  
Type I ◽  
Type Ii ◽  
Electron Microscopic ◽  
Deciduous Molars ◽  
Scanning Electron

Under the scanning electron microscope, the characteristics of the buccal surface enamel of human non-erupted deciduous molars were evaluated after using 15, 30, and 45 seconds of phosphoric acid etching time. The teeth were extracted, kept in a 70% alcohol solution and later dehydrated and metallized for analysis with the scanning electron microscope JEOL, JSM-6.100. The in vitro experiment with 35% phosphoric acid revealed that there is a tendency of predominance of interprismatic enamel dissolution or type II pattern with 15 and 45 seconds etching time. The dissolution of the interprismatic enamel was more pronounced when an acid etching time of 45 seconds was used. The enamel surface demonstrated type I and type II patterns when acid etching time was 30 seconds

scholarly journals Immunocytochemical localization of glycoprotein hormones in the rat anterior pituitary. A light and electron microscope study using antisera against rat bet subunits: a comparison between preembedding and postembeeding methods.

1980 ◽  
Vol 28 (2) ◽  
pp. 101-114 ◽  
Author(s):  
C Tougard ◽  
R Picart ◽  
A Tixier-Vidal
Keyword(s):  
Electron Microscope ◽  
Binding Sites ◽  
Secretory Granules ◽  
Periodic Acid ◽  
Light And Electron Microscopy ◽  
Thyroid Stimulating Hormone ◽  
Periodic Acid Schiff ◽  
Thyrotropic Cells ◽  
Rat Thyroid ◽  
Stimulating Hormone

The binding sites of antisera (anti) to the beta (beta) subunits of rat follicle-stimulating hormone (rFSH), rat luteinizing hormone (rLH), and rat thyroid-stimulating hormone (rTSH) have been localized in rat anterior pituitaries by immunocytochemistry using light and electron microscopy. With the light microscope, LHbeta and FSHbeta were found in the same cells, which were violet after the alcian blue-periodic acid Schiff (AB-PAS) staining. TSHbeta was found in polygonal or stellate cells that were blue after AB-PAS. With the electron microscope, the thyrotropic cells contained very small secretory granules. LHbeta and FSHbeta were found in various types of cells (types A and B and their intermediate forms), which had previously been identified as gonadotropic cells. On serial ultrathin sections using the postembedding method the same cells and even some granules inside these cells were stained by both anti-rLHbeta and anti-rFSHbeta. A comparison of binding sites of anti-rLHbeta was performed using the preembeeding and the postembeeding methods. Antigenicity was observed on secretory granules whatever the method used. However, binding sites of anti-rLHbeta were detected inside the cisternae of the rough endoplasmic reticulum only with the preembedding method.

Vertebrate liver cytokeratins: a comparative study

1987 ◽  
Vol 65 (6) ◽  
pp. 547-557 ◽  
Author(s):  
R. G. Pankov ◽  
A.A. Uschewa ◽  
B. T. Tasheva ◽  
G. G. Markov
Keyword(s):  
Electron Microscopy ◽  
Molecular Weight ◽  
Intermediate Filaments ◽  
Methodological Approach ◽  
Type I ◽  
Type Ii ◽  
Electron Microscopic ◽  
Intermediate Filament Proteins ◽  
Lower Vertebrates ◽  
Microscopic Morphology

The structure and composition of intermediate filaments isolated from liver of representatives of different vertebrate classes have been studied by electron microscopy and biochemical and immunochemical methods. It has been shown that the methodological approach for isolation of rat liver intermediate filaments can be efficiently applied to all other classes of vertebrates. The intermediate filaments studied have the same electron microscopic morphology and are species undistinguishable. The molecular weight of intermediate filament proteins varies from 40 000 to 60 000 and their isoelectric point varies from 5.0 to 6.45. Immunological investigations show that in all animals studied the intermediate filaments are built up of cytokeratins belonging to both types of keratins: type I and type II. Only one protein of the type II cytokeratins is present in all vertebrate classes, whereas in lower vertebrates two or even three type I cytokeratins contribute to the structure of liver intermediate filaments. The biochemical and immunochemical results are discussed with regard to the evolution of liver cytokeratins.

scholarly journals Application of a rapid avidin--biotin--peroxidase complex (ABC) technique to the localization of pituitary hormones at the electron microscopic level.

1982 ◽  
Vol 30 (12) ◽  
pp. 1320-1324 ◽  
Author(s):  
G V Childs ◽  
G Unabia
Keyword(s):  
Staining Intensity ◽  
Thyroid Stimulating Hormone ◽  
Electron Microscopic Level ◽  
Pituitary Cells ◽  
Electron Microscopic ◽  
High Background ◽  
Prolonged Incubation ◽  
Abc Method ◽  
Rat Thyroid ◽  
Stimulating Hormone

The new avidin--biotin--peroxidase complex (ABC) technique was applied to ultrathin sections of rat pituitary that were fixed with glutaraldehyde and embedded in Araldite 6005. The primary antisera dilutions that are normally applied for 24-48 hr with the peroxidase-antiperoxidase (PAP) complex technique were used. High background was observed with the ABC method when incubation times were 12-48 hr. Tests were then conducted with shorter incubation times. The staining intensity was measured with a densitometer. Detectable stain was seen after only 15 min in dilutions of 1:10,000 anti-bovine luteinizing hormone (bLH beta), 1:8000 anti-rat thyroid-stimulating hormone (rTSH beta), and 1:20,000 anti-25-39-adrenocorticotropic hormone (25-39ACTH). Optimal LH staining was seen after 30 min, whereas optimal staining for TSH or ACTH required 1 hr. Stain was detectable with a dilution of 1:4000 anti-human follicle-stimulating hormone (hFSH beta) after 30 min and was optimal after 4 hr. Prolonged incubation times with these dilutions decreased the staining intensity because a deposit of high background was produced that appeared as a filigreed network over the cells. When higher dilutions were tested with 2-hr incubation times, optimal staining was seen with 1:30,000 anti-bLH beta, 1:24,000 anti-rTSH beta, 1:30,000 anti-25-39ACTH, and 1:8000 anti-hFSH beta. These tests demonstrate the potential of the ABC method for the rapid detection of small amounts of specific and nonspecific antibodies that are bound to pituitary cells.

scholarly journals Accumulation of Major Histocompatibility Complex Class II Molecules in Mast Cell Secretory Granules and Their Release upon Degranulation

1997 ◽  
Vol 8 (12) ◽  
pp. 2631-2645 ◽  
Author(s):  
Graça Raposo ◽  
Danielle Tenza ◽  
Salahedine Mecheri ◽  
Roger Peronet ◽  
Christian Bonnerot ◽  
...  
Keyword(s):  
Mast Cell ◽  
Major Histocompatibility Complex ◽  
Mhc Class Ii ◽  
Secretory Granules ◽  
Class Ii ◽  
Type I ◽  
Type Ii ◽  
Histocompatibility Complex ◽  
Secretory Lysosomes ◽  
Mhc Class Ii Molecules

To investigate the relationship between major histocompatibility complex (MHC) class II compartments, secretory granules, and secretory lysosomes, we analyzed the localization and fate of MHC class II molecules in mast cells. In bone marrow-derived mast cells, the bulk of MHC class II molecules is contained in two distinct compartments, with features of both lysosomal compartments and secretory granules defined by their protein content and their accessibility to endocytic tracers. Type I granules display internal membrane vesicles and are accessed by exogenous molecules after a time lag of 20 min; type II granules are reached by the endocytic tracer later and possess a serotonin-rich electron-dense core surrounded by a multivesicular domain. In these type I and type II granules, MHC class II molecules, mannose-6-phosphate receptors and lysosomal membrane proteins (lamp1 and lamp2) localize to small intralumenal vesicles. These 60–80-nm vesicles are released along with inflammatory mediators during mast cell degranulation triggered by IgE-antigen complexes. These observations emphasize the intimate connection between the endocytic and secretory pathways in cells of the hematopoietic lineage which allows regulated secretion of the contents of secretory lysosomes, including membrane proteins associated with small vesicles.

An immunocytochemical and electron microscopic study of the hyt mouse anterior pituitary gland

1986 ◽  
Vol 109 (2) ◽  
pp. 163-NP ◽  
Author(s):  
T. Noguchi ◽  
M. Kudo ◽  
T. Sugisaki ◽  
I. Satoh
Keyword(s):  
Endoplasmic Reticulum ◽  
Rough Endoplasmic Reticulum ◽  
Anterior Pituitary ◽  
Mutant Mouse ◽  
Secretory Granules ◽  
Somatic Growth ◽  
Thyroid Stimulating Hormone ◽  
Ideal Model ◽  
Electron Microscopic ◽  
Thyrotrophin Releasing Hormone

ABSTRACT The hyt mutant mouse used in this study has a hypoplastic thyroid gland and is characterized by retarded somatic growth, very low to undetectable levels of plasma thyroxine (T4), and increased levels of plasma thyroid-stimulating hormone (TSH). This congenital hypothyroid mouse is therefore an ideal model for studying the effects of thyroid hypofunction on the adenohypophysis. The anterior pituitary of the hyt mouse appeared less granular than that of the normal control when viewed by light microscopy, owing to a decrease in the population of somatotrophs. Many cells, in various stages of transformation into 'thyroidectomy cells', were recognized by the appearance of the characteristic granules and dilated rough endoplasmic reticulum. In some cases, the enlarged rough endoplasmic reticulum also contained spherical electron-dense secretory granules. In addition there were many cells undergoing mitosis and these were identified as thyrotrophs by their characteristic granules. Administration of T4 during the first 40 days of life prevented the abnormal changes in the hyt anterior pituitary. A reduction in immunoreactive thyrotrophin-releasing hormone (TRH) levels was seen in the median eminence of the hyt mouse. Treatment with T4 restored this to normal, suggesting that the reduced TRH content of the hypothalamus of the mutant mouse may be due to T4 deprivation. J. Endocr. (1986) 109, 163–168

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