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.

scholarly journals LIGHT AND ELECTRON MICROSCOPE LOCALIZATION OF BINDING SITES OF ANTIBODIES AGAINST OVINE LUTEINIZING HORMONE AND ITS TWO SUBUNITS IN RAT ADENOHYPOPHYSIS USING PEROXIDASE-LABELED ANTIBODY TECHNIQUE

1973 ◽  
Vol 58 (3) ◽  
pp. 503-521 ◽  
Author(s):  
C. Tougard ◽  
B. Kerdelhue ◽  
A. Tixier-Vidal ◽  
M. Jutisz
Keyword(s):  
Electron Microscope ◽  
Luteinizing Hormone ◽  
Binding Sites ◽  
Secretory Granules ◽  
Periodic Acid ◽  
Light And Electron Microscopy ◽  
Type A ◽  
Periodic Acid Schiff ◽  
Antibody Technique ◽  
A Cells

The binding sites of antisera generated in the guinea pig against ovine luteinizing hormone (oLH) and its two subunits (oLHα and oLHß) have been localized in rat anterior pituitaries taken from normal or castrated males and from ovariectomized females with the peroxidase-labeled antibody method, using light and electron microscopy. With the light microscope, the cells positive with antiserum to ovine luteinizing hormone (A-oLH) were violet after the Alcian blue-periodic acid-Schiff (AB-PAS) staining; they were also positive for A-oLHα and for A-oLHß and, from castrated males, they displayed an increased affinity for A-oLHß. Another cell type which was blue after the AB-PAS method reacted with the A-oLHα only; these cells, presumably thyrotropic cells, were retracted after castration and, besides their affinity for A-oLHα, acquired an affinity for A-oLHß. As seen through the electron microscope, two cell types were positive for A-oLH, A-oLHß, and A-oLHα and may be identified as luteinizing hormone-secreting cells. Type A cells were characterized by two classes of rounded, secretory granules. Type B cells were smaller and contained only small secretory granules. 1 mo after the rats were castrated the type A cells were hypertrophied and vacuolized. In both cases the secretory granules were the main sites of the antigenicity with the three antisera. A positive reaction was also found in the cytoplasm, particularly in hypertrophied cells from ovariectomized females and with A-oLHß. The cisternae of the rough endoplasmic reticulum were usually negative, except in highly degranulated cells from ovariectomized females and with A-oLHß.

scholarly journals CORRELATED LIGHT AND ELECTRON MICROSCOPE OBSERVATIONS ON GLYCOPROTEIN-CONTAINING GLOBULES IN THE FOLLICULAR CELLS OF THE THYROID GLAND OF THE RAT

1965 ◽  
Vol 13 (4) ◽  
pp. 286-295 ◽  
Author(s):  
HUBERTA E. VAN HEYNINGEN
Keyword(s):  
Electron Microscope ◽  
Thyroid Gland ◽  
Toluidine Blue ◽  
Fine Particles ◽  
Periodic Acid ◽  
Follicular Cells ◽  
Periodic Acid Schiff ◽  
Intense Staining ◽  
Thin Sections ◽  
Rat Thyroid

Two carbohydrate staining techniques were applied to sections of rat thyroid gland: periodic acid-silver methenamine to thin sections for electron microscopy, and periodic acid-Schiff to thick sections for light microscopy. The latter were compared with adjacent thin sections for identificatoin with the electron microscope. Two types of globules in thyroid follicular cells stained with both methods. Globules of the first type are relatively large (usually 0.5 to 3 µ) with electron opacity very similar to that of follicular colloid; when stained with toluidine blue they have the same gray shade as follicular colloid. These similarities suggest that their periodic acid reactivity is due to the same glycoprotein as that of follicular colloid, namely thyroglobulin, and that the origin of these "intracellular colloid droplets" is the colloid in the lumen. The second type comprises medium-sized (usually 0.1 to 1 µ) fairly electron opaque globules having fine particles (~70 Å) dispersed in their matrices and sometimes containing membrane fragments or other irregularities; when stained with toluidine blue these globules stand out dark blue. Although their periodic acid reactivity indicates that these globules also contain glycoprotein, their ultrastructure and staining characteristics suggest that their composition differs from colloid. It is possible that they represent enzyme or zymogen-containing granules. A third type of globule, which on account of its intense staining in some periodic acid silver methenamine preparations could perhaps also be periodic acid reactive, concerns small (usually 0.02 to 0.2 µ) globules, mainly accumulated beneath the apical border of the cell. These globules, known as "apical vesicles," are believed to contain the not-yet-iodinated precursor of thyroglobulin.

Prefertilization ovule development in Capsella: the dyad, tetrad, developing megaspore, and two-nucleate gametophyte

1986 ◽  
Vol 64 (4) ◽  
pp. 875-884 ◽  
Author(s):  
Patricia Schulz ◽  
William A. Jensen
Keyword(s):  
Cell Wall ◽  
Electron Microscope ◽  
Acid Phosphatase ◽  
De Novo ◽  
Periodic Acid ◽  
Aniline Blue ◽  
Ovule Development ◽  
Periodic Acid Schiff ◽  
Fluorescent Material ◽  
Autophagic Vacuoles

Ovules of Capsella bursa-pastoris at the dyad and tetrad stages of meiosis and at the megaspore and two-nucleate stages of the gametophyte were studied with the electron microscope. The cells of the dyad and tetrad are separated by aniline blue fluorescent cross walls and receive all types of organelles and autophagic vacuoles that were present in the meiocyte. Autophagic vacuoles enclose ribosomes and organelles and show reaction product for acid phosphatase. Autophagic vacuoles and some plastids are absorbed into the enlarging vacuoles of the growing megaspore. Other plastids appear to survive meiosis and there is no evidence for their de novo origin. Some mitochondria appear to degenerate in the enlarging megaspore but others look healthy and there is no evidence for the de novo origin of mitochondria. The nucleolus of the developing megaspore becomes very large and the cytoplasm is extremely dense with ribosomes. The cell wall is thickened by an electron-translucent, periodic acid – Schiff negative, aniline blue fluorescent material and contains plasmodesmata that link the megaspore with the nucellus. The plasmalemma of the growing megaspore produces microvilluslike extensions into this wall that disappear with the formation of the two-nucleate gametophyte. Plasmodesmata disappear from the cell wall at the four-nucleate stage.

Pituitary Adenomas that Produce Adrenocorticotropic Hormone and A-Subunit: Clinicopathological, Immunohistochemical, Ultrastructural, and Immunoelectron Microscopic Studies in Nine Cases

Neurosurgery ◽  
1990 ◽  
Vol 26 (3) ◽  
pp. 397-403 ◽  
Author(s):  
Kathryn K. Berg ◽  
Bernd W. Scheithauer ◽  
Ignacio Felix ◽  
Kalman Kovacs ◽  
Eva Horvath ◽  
...  
Keyword(s):  
Pituitary Adenomas ◽  
Adrenocorticotropic Hormone ◽  
Secretory Granules ◽  
Preoperative Evaluation ◽  
Periodic Acid ◽  
Periodic Acid Schiff ◽  
Double Labeling ◽  
Corticotroph Adenoma ◽  
A Subunit ◽  
Corticotroph Adenomas

Abstract Eight surgical and one autopsy specimen of pituitary adenomas (six cases of Cushing's disease, two of Nelson's syndrome. and one of hypopituitarism) were studied by histochemical, immunohistocytological, and ultrastructural methods. Eight tumors showed the characteristic histochemical profile of corticotroph adenoma—amphophilic to basophilic, and periodic acid-Schiff-positive to some extent. In all tumors, immunohistochemical studies revealed adrenocorticotropic hormone (ACTH) and à-subunit in the cytoplasm of some adenoma cells. By electron microscopy, seven tumors were found to be monomorphous; six were typical corticotroph adenomas and one was a subtype II silent corticotroph adenoma. One unique lesion was bimorphous—i.e., composed of corticotrophs as well as cells resembling glycoprotein cells. Immunoelectron microscopy by the double-labeling immunogold technique, performed on one corticotroph adenoma, demonstrated the presence of ACTH and à-subunit not only within the same adenoma cells but also within the same secretory granules. The cytogenesis of ACTH à-subunit tumors, a rare form of plurihormonal adenoma. remains to be elucidated. The duration of disease associated with these tumors exceeded the duration in patients with ordinary corticotroph adenomas. Given the low frequency with which increases in serum à-subunit are detectable in patients with such tumors—13% in this series—hormone production is not recognized at preoperative evaluation.

scholarly journals Immunochemical characterization of two thyroid-stimulating hormone β-subunit epitopes

1995 ◽  
Vol 308 (1) ◽  
pp. 203-210 ◽  
Author(s):  
W D Fairlie ◽  
P G Stanton ◽  
M T W Hearn
Keyword(s):  
Receptor Binding ◽  
Binding Sites ◽  
Thyroid Stimulating Hormone ◽  
Beta Subunit ◽  
Human Thyroid ◽  
Lysine Residues ◽  
Sequence Region ◽  
The Relationship ◽  
Stimulating Hormone

The epitopes of human thyroid-stimulating hormone (hTSH) recognized by two murine monoclonal antibodies (MAbs), designated MAb 279 and MAb 299, have been characterized. These MAbs are highly specific for the beta-subunit of TSH. The epitope recognized by MAb 279 appears to be completely conserved between bovine and human TSH and partially conserved in the porcine species. The TSH beta-subunit epitope recognized by MAb 299 is only partially conserved between the human, bovine and porcine species. Both MAbs are capable of inhibiting the binding of TSH to its receptor in a TSH radioreceptor assay, indicating that the epitopes either coincide or are located close to the TSH beta-subunit receptor-binding sites. The carbohydrate moieties of the TSH beta-subunit appear to play little or no role in the epitope recognition by MAb 279 or MAb 299 while the integrity of the disulphide bonds are essential. The epitopic recognition may also involve lysine residues, as determined by the immunoreactivity with both MAbs following citraconylation of TSH. In addition, the amino acid sequence region between residues bTSH beta 34-44 could be excised by trypsin digestion of bovine TSH beta (bTSH beta) without eliminating epitopic recognition by either MAb. These results provide further insight into the relationship between the structure of the TSH beta-subunit epitopes and location of the receptor-binding sites.

scholarly journals Changes in tight junctions of thyroid epithelium with changes in thyroid activity.

1975 ◽  
Vol 66 (3) ◽  
pp. 657-663 ◽  
Author(s):  
L W Tice ◽  
S H Wollman ◽  
R C Carter
Keyword(s):  
Tight Junction ◽  
Tight Junctions ◽  
Cell Types ◽  
Thyroid Stimulating Hormone ◽  
Thyroid Activity ◽  
Short Term ◽  
Rat Thyroid ◽  
Thyroid Epithelium ◽  
Stimulating Hormone

The morphology of the tight junction of rat thyroid epithelium was examined in freeze-fractured material fixed in glutaraldehyde and briefly glycerinated. In normal thyroids the overall appearance of this junctional specialization resembled that of other cell types in many respects. Short-term changes in thyroid activity and hypophysectomy for 3 wk did not obviously affect the appearance of tight junctions. Feeding of the goitrogen, thiouracil, which stimulates secretion of thyroid-stimulating hormone, resulted in the appearance of some very narrow and some very wide, tight junctions or sometimes junctions with both wide and narrow regions within the same cell.

The effects of propylthiouracil, thyroxine, and hypophysectomy on the iodinating activity of the rat thyroid gland

1968 ◽  
Vol 46 (3) ◽  
pp. 449-452 ◽  
Author(s):  
A. E. Zimmerman ◽  
C. C. Yip
Keyword(s):  
Drinking Water ◽  
Thyroid Gland ◽  
Thyroid Stimulating Hormone ◽  
Rapid Decrease ◽  
Daily Injection ◽  
The Third ◽  
Thyroxine Treatment ◽  
Rat Thyroid ◽  
Rat Thyroid Gland ◽  
Stimulating Hormone

The effects of increasing or decreasing the endogenous secretion of thyroid-stimulating hormone on the iodinating activity of the rat thyroid gland were investigated. The thyroid iodinating activity of rats on 0.01% propylthiouracil in the drinking water increased linearly for 3 days and reached a maximum of 230 to 240% of the control on or about the fourth day of treatment. The daily injection of thyroxine (10 μg/100 g intraperitoneally) or hypophysectomy resulted in a rapid decrease in the iodinating activity between the first and second day, approaching a basal level by the third day. When the iodinating activity was suppressed for 4 days by daily injections of thyroxine, the activity began to rise on the fifth day after termination of thyroxine treatment.

An ultrastructural comparison of soft and hardened spermatophores from the crayfish Pacifastacus leniusculus Dana

1983 ◽  
Vol 61 (1) ◽  
pp. 182-194 ◽  
Author(s):  
E. E. Dudenhausen ◽  
P. Talbot
Keyword(s):  
Structural Changes ◽  
Periodic Acid ◽  
Light And Electron Microscopy ◽  
Outer Region ◽  
Middle Layer ◽  
Pacifastacus Leniusculus ◽  
Periodic Acid Schiff ◽  
Structural Modifications ◽  
Inner Region ◽  
Region Ii

The spermatophore of the crayfish Pacifastacus leniusculus consists of two main parts: a sperm mass composed of sperm embedded in a dense fibrillar matrix and an acellular wall which surrounds the sperm mass and is formed from secretions produced in the vas deferens. Following extrusion from the male, the spermatophore wall, which is initially soft and sticky, undergoes a hardening process. In this study, the structure of the spermatophore walls of unextruded (soft) and hardened spermatophores were compared using light and electron microscopy. The wall of the unextruded spermatophore is composed of three concentric layers: a thin primary spermatophore layer which directly surrounds the sperm mass; a thick middle layer composed primarily of electron-dense, spherical granules; and a thick outer layer formed from a dense globular secretion. The primary spermatophore layer and outer globular layer are positive for carbohydrate with the periodic acid – Schiff method. Following extrusion and hardening, the walls of spermatophores showed several structural changes. These are (i) division of the middle granular layer into a compact inner region and a highly reticulated outer region; (ii) the loss of the outer globular layer; and (iii) the formation of a thickened ridge along one side of the spermatophore wall. The thickened ridge is fibrillar in structure and is believed to be derived from a structural modification of the outer globular layer. No structural modifications in the primary spermatophore layer were observed. We interpret these observations to indicate that the outer globular layer functions in attachment of the spermatophore to the female and the middle layer is involved in spermatophore hardening and sperm protection during storage.

Changes in surface morphology of pigmented retinal cells during differentiation in clonal culture

1981 ◽  
Vol 59 (1) ◽  
pp. 61-69 ◽  
Author(s):  
B. J. Crawford ◽  
Alex Yan ◽  
M. MacDonald
Keyword(s):  
Electron Microscope ◽  
Surface Morphology ◽  
Periodic Acid ◽  
Outer Edge ◽  
Gradual Change ◽  
Apical Surface ◽  
Periodic Acid Schiff ◽  
Clonal Culture ◽  
Cellular Attachment

The changes in surface morphology during the reexpression of differentiation of chick retinal pigmented epithelial cells (RPE) in clonal culture have been studied using the scanning electron microscope (SEM) and transmission electron microscope (TEM) and compared with those described in vivo. Three-week-old colonies demonstrated a gradual change in apical surface morphology along any colony radius. At the outer edge, the cell surfaces were either smooth with a few small filamentous protrusions or showed a varying number of large blebs. Toward the centre of the colony the surfaces demonstrated a gradual increase in filamentous protrusions. The apical surfaces of the most densely pigmented cells at the centre of the colony consisted mainly of small rounded protrusions. The changes in surface morphology of cells in the centre of younger colonies during redifferentiation were similar to those found along the radius of a 3-week-old colony. The results show that older colonies have all of the morphological stages of the redifferentiation process (and possibly the biochemical ones as well) arranged along any radius.The basal surfaces of all the colonies were covered by a thin acellular membrane that stained positively with periodic acid–Schiff (PAS) and which may contain fibronectins and appears to be involved in cellular attachment.

Sign in / Sign up

Export Citation Format

Share Document