Demonstration of glial fibrillary acidic (GFA) protein by electron immunocytochemistry in the granular cells of a choristoma of the neurohypophysis

1991 ◽  
Vol 96 (3) ◽  
pp. 265-269 ◽  
Author(s):  
S. A. Vinores
Keyword(s):  
Granular Cells ◽  
Gfa Protein ◽  
Electron Immunocytochemistry

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).

Adrenomedullin Stimulates Renin Release and Renin mRNA in Mouse Juxtaglomerular Granular Cells

Hypertension ◽  
1997 ◽  
Vol 29 (5) ◽  
pp. 1148-1155 ◽  
Author(s):  
Boye L. Jensen ◽  
Bernhard K. Krämer ◽  
Armin Kurtz
Keyword(s):  
Renin Release ◽  
Granular Cells ◽  
Renin Mrna

scholarly journals Cyclic AMP selectively increases renin mRNA stability in cultured juxtaglomerular granular cells.

1993 ◽  
Vol 268 (32) ◽  
pp. 24138-24144
Author(s):  
M Chen ◽  
J Schnermann ◽  
A.M. Smart ◽  
F.C. Brosius ◽  
P.D. Killen ◽  
...  
Keyword(s):  
Cyclic Amp ◽  
Mrna Stability ◽  
Granular Cells ◽  
Renin Mrna

Desmosomes in hamster cheek pouch epithelium: their quantitative characterization during epithelial differentiation

1984 ◽  
Vol 66 (1) ◽  
pp. 411-429
Author(s):  
F.H. White ◽  
K. Gohari
Keyword(s):  
Plasma Membrane ◽  
Surface Area ◽  
Cheek Pouch ◽  
Unit Surface Area ◽  
Granular Cells ◽  
Hamster Cheek Pouch ◽  
Average Cell ◽  
Membrane Area ◽  
The Mean ◽  
Granular Layers

Desmosomes in stratified squamous epithelia appear to exhibit quantitative alterations during differentiation. In this work we use stereological and other morphometric methods to quantify these structures in epithelial cells from defined basal, spinous and granular strata. Hamster cheek pouch mucosa from five animals was processed for electron microscopy using strictly standardized techniques and a stratified random sampling procedure was used to obtain micrographs of cells from basal, spinous and granular layers. Stereological intersection counting techniques were used to determine for each layer the relative surface area of plasma membrane occupied by desmosomes (Ss), the number of desmosomes per unit surface area of plasma membrane (Ns), the mean individual desmosomal diameter (delta) and the mean individual desmosomal surface area (s). In addition, estimates of nuclear volume were obtained by direct measurement of nuclear profiles and volume-to-surface ratios were obtained by a combination of point and intersection counting, which enabled estimates for the volume (Vcell) and plasma membrane surface area (SPM) of the ‘average’ cell within each stratum to be acquired. Using this information, it was then possible to calculate both the total surface area (S) and the number (N) of desmosomes on the plasma membranes of average cells. The parameters Ss and Ns showed progressive increases between basal and granular layers, whereas values for delta and s were lower in granular cells when compared with basal and spinous cells. The parameters Vcell, SPM, S and N all increased progressively and significantly during differentiation. Between basal and granular layers, the mean cell volume and surface area had each increased approximately threefold, whereas the surface area and number of desmosomes on the average cell plasma membrane had increased approximately seven- and eleven-fold, respectively. Granular cells thus possess more numerous desmosomes, which occupy a greater proportion of the plasma membrane area but which are individually smaller, when compared with basal and spinous layers.

Effect of changes in extracellular Cl on intracellular Cl activity in frog skin

1988 ◽  
Vol 254 (1) ◽  
pp. F95-F104 ◽  
Author(s):  
K. Drewnowska ◽  
T. U. Biber
Keyword(s):  
Frog Skin ◽  
Rana Pipiens ◽  
Initial Rate ◽  
Apical Cell ◽  
Disulfonic Acid ◽  
Free Solution ◽  
Granular Cells ◽  
Apical Side ◽  
Basolateral Side ◽  
Cl Permeability

Intracellular Cl activity was measured in isolated frog skin (Rana pipiens) with double-barrel microelectrodes. The initial rate of Cl uptake was measured in Cl-depleted cells on reexposure to Cl on apical or basolateral side. In skins with high and low conductance, cell CL activity increased 1.33 and 0.14 mM/s with apical reexposure and 5.03 and 0.30 mM/s with basolateral reexposure, respectively. The initial Cl uptake was reduced on the apical side by 93% with 10(-3) M DIDS (4,4'-diisothiocyanostilbene-2,2ߗ-disulfonic acid) and on the basolateral side by 99% with 10(-3) M SITS (4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonic acid) plus 10(-5) M bumetanide. The initial rate of Cl loss was measured when Cl was removed from the bath: addition of HCO3 to Cl- and HCO3-free solution caused an acceleration of Cl loss in absence but not in presence of DIDS on apical side. In contrast, Cl loss across the basolateral side was not enhanced by HCO3. In conclusion, Na-transporting cells have a substantial Cl permeability on both sides. HCO3-stimulated Cl loss provides evidence for Cl-HCO3 exchange and permits localization of this process in apical cell membranes of granular cells.

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