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K Gorgas

Publications and source records attributed to K Gorgas.

53 records · Page 3Linked to original sources
PubMed1977

Morphology and histochemistry of helicine arteries in the corpora cavernosa penis of mice.

The epitheloid modified walls of helicine arteries are built of tightly arranged specialized smooth muscle cells (epitheloid cells). They are polygonal in shape, but do not branch out. The number of myofilaments is markedly reduced, whereas cell organelles are well developed (mitochondria, Golgi regions, rough endoplasmic reticulum). Myofilaments are gathered to bundles with no orientation as to their direction. Regular dense patches and attachment zones do occur. The cell surface is provided with caveolae (surface vesicles) and a basal lamina. Where epitheloid cells are joined together, they share a single basal lamina in common. In circumscribed regions basal lamina material is completely absent, and the cell membranes approach to form a 150 A gap (paired cells). Endothelial cells are rich in cytoplasmic filaments and show only a few transport vesicles. In particular areas a basal lamina is absent, and epitheloid cells and endothelial cells are joined together leaving a 200 A wide cleft. Fluorescence histochemistry shows that helicine arteries are provided with an extremely dense network of adrenergic nerves located at the medio-adventitial border. Epitheloid cells, like ordinary vascular smooth muscle cells, show a postive ATPase reaction, but lack any histochemically demonstrable 5'-nucleotidase activity. Endothelial cells in helicine arteries react on unspecific alkaline phosphatase, while the endothelium of deep arteries and of the cavernous spaces does not.

Animals↗
PubMed1977

Fine structure of a bronchial oncocytoma.

The fine structure of a bronchial oncocytoma is described. The tumour cells are characterized by abundant, normal sized mitochondria with lamellar cristae. Membrane bound protein granules, which measure 0,1 to 0.5 micron in diameter, are also regularly found. Furthermore, all cell organelles involved in protein synthesis occur in oncocytes. The tumour cells lack basement membranes. The protein storing granules of oncocytes are comparable to peptide hormones storing granules. Positive staining with lead hematoxylin and a faint argentaffin staining suggest that oncocytes in the case studied belong to an oncocytic carcinoid. This view is further substantiated by a high serotonin content of the tumour (50.6 microgram/g wet weight).

Aged↗
PubMed1976

Morphology and histochemistry of the adrenal medulla. I. Various types of primary catecholamine-storing cells in the mouse adrenal medulla.

Semithin sections (Araldite) of mouse adreno-medullary tissue were examined in the light microscope after perfusion fixation with glutaraldehyde, glutaraldehyde/formaldehyde or after freeze-drying followed by a treatment with hot formaldehyde gas. The following methods were employed: (i) aldehyde-induced fluorescence of catecholamines, (ii) Schmorl's ferric ferricyanide reaction, (iii) argentaffin reaction, and (iiii) staining with alkaline lead citrate followed by Timm's silver sulphide reaction. The correspondence of results obtained by the various methods was proven in consecutive sections or by successively applying different methods to identical sections. Four types of primary catecholamine-storing cells were identified. NA1 cells contain cytoplasmic granules up to 0.3 mum in diameter which stain black with ammoniacal silver and display a bright white to yellow fluorescence. NA2 cells show smaller cytoplasmic granules which stain brown with the argentaffin method and give white catecholamine fluorescence. NA3 cells appear yellow-earth after applying the argentaffin reaction and show greenish fluorescence. NA4 cells are hardly identified in the light microscope. These cells are significantly smaller than the above mentioned cells and characterized by a high nucleo-cytoplasmic ratio. They become straw coloured with ammoniacal silver and show greenish fluorescence. The argentaffin reaction was also used to identify these cells in semithin sections of glutaraldehyde/osmium tetroxide fixed material. The fine structure of the various noradrenalin-storing cells was studied in consecutive thin sections. NA1 cells were found to contain two populations of granules, the larger ones measuring between 300 and 350 nm, the smaller ones about 175 nm. The granules in NA2 cells correspond to this latter population (175 nm). NA3 cells contain an uniform granule population with a main diameter of 120 nm. The smallest granules are seen in NA4 cells being in the dimension of 80 nm. Granules in NA1 and NA2 cells show uniformly high density, whereas those in NA3 and NA4 cells display cores of varying density. Granules with moderately dense cores in NA3 and NA4 cells may represent partially emptied sites of noradrenalin storage or dopamin containing particles.

Adrenal Medulla↗
PubMed1976

Formaldehyde induced catecholamine fluoroscence in the mouse inferior laryngeal paraganglion.

The presence of high concentrations of catecholamines is shown in the mouse's inferior laryngeal paraganglion by means of fluorescence histochemistry. In mice, the entire organ is composed of 20 to 25 small, intensely fluorescent cells of oval shape (about 15 mum in diameter). The paraganglion is well provided with capillaries. The identification of catecholamines in the inferior laryngeal paraganglion, originally described as nonchromaffin (parasympathetic) paraganglion, presents additional evidence that all paraganglia store biogenic amines, are related to the sympathetic nervous system, and belong to the APUD cell series.

Animals↗
PubMed1976

Studies on intra-arterial cushions. II. Distribution of horseradish peroxidase in cushions at the origins of intercostal arteries in mice.

The distribution of horseradish peroxidase (HRP) in intraarterial cushions at the origins of intercostal arteries was studied in mice 30 min after intravenous injection of the tracer. HRP is found to be evenly distributed in the extracellular space of the entire arterial wall. Basal lamina material is penetrated by the tracer protein. This is not the case with collagenic fibrils, elastic material and intercellular granular deposits which occur regularly in cushions of adult mice but not in those of newborn animals (granules 300 to 800 A in diameter, probably cell debris). However, the elastic sheets do not act as diffusion barriers. HRP is not phagocytized in significant amounts by ramified smooth muscle cells within the time intervals tested. It is therefore assumed that granular deposits are also not phagocytized by smooth muscle cells.

Animals↗
PubMed1976

Fine structure of baroreceptor terminals in the carotid sinus of guinea pigs and mice.

A light and electron microscopic study was undertaken on the baroreceptor axon terminals in the carotid sinus of guinea pigs and mice, using serial semithin and thin sections. Together with their enveloping Schwann cells, numerous lanceolate axon terminals are organized into a well-defined discoid end organ, referred to as the 'baroreceptor unit'. Baroreceptor units measure 100 to 150 mum in diameter and are arranged in a hexagonal pattern. These end organs represent free branched lanceolate mechanoreceptors of complex type (Andres and von Düring, 1973) which belong to the main group of stretch receptors. In the guinea pig the lanceolate terminals enter the media and approach the innermost layers near the intima. In the mouse the terminals are seen to spread in the adventitia and along the medio-adventitial border. Only a few of them penetrate the external elastic layer. Species differences concerning the localization and extent of these visceral mechanoreceptors are discussed, as well as the modified architecture of the sinus wall in the receptor area ('elastic segment'). Lanceolate terminals form beaded varicosities which are equipped with finger-like or lamellar exoplasmic protrusions. These projections contain a well-differentiated receptor matrix. They are attached to collagen and elastic fibers. The varicosities include densely packed mitochondria, neurotubules, profiles of axoplasmic reticulum, clear and granular vesicles, and striking accumulations of glycogen particles, lamellated bodies and lysosomes. Four types of varicosities are discerned according to their main axoplasmic components. Various types of these varicosities occur within an individual lanceolate terminal.

Animals↗
PubMed1976

Alkaline lead citrate: a selective stain for glutaraldehyde precipitates of indolamines and primary catecholamines in electron microscopy.

Test-tube experiments proved that alkaline lead citrate (Reynolds, 1963), which is generally used as an electron-opaque stain, specifically reacts with precipitates formed by glutaraldehyde and biogenic amines (indolamines, primary catecholamines). Glutaraldehyde/osmium tetroxide fixation and staining of thin sections with alkaline lead citrate is recommended as an optimal preparation method of studying the above-mentioned amines at a fine structural level.

Adrenal Medulla↗
PubMed1976

Fine structure of a virilizing adrenocortical adenoma.

An adrenocortical adenoma associated with adrenogenital syndrome in a two-year-old boy was investigated light and electron microscopically. Urinary 17-ketosteroid excretion was considerably elevated and unresponsive to dexamethasone administration. The level returned to normal after surgical removal of the tumour. Adenomatous cells display striking cellular and nuclear pleomorphism. Megalocytes with huge nuclei and nucleoli frequently occur. Deep cytoplasmic indentations cause nuclear pseudoinclusions and bizarre shape of the nuclei. True nuclear inclusions are also seen, as well as nuclear fragmentation. Cytoplasmic organelles show striking morphological alterations. Mitochondria with lamellar and tubular cristae are transformed into round or ovoid organelles of vesicular type. Their internal compartment is reduced, matrix material increases relatively, and mitochondrial inclusion bodies develop. Mitochondrial inclusions are identified as corresponding to fuchsinophil (siderophil or argyrophil) granules seen in the light microscope. Their staining properties indicate their glycoprotein nature. Vesicular profiles of smooth endoplasmic reticulum predominate and stacks of rough endoplasmic reticulum are transformed into tubules and vesicles. In Golgi regions, only vesicular elements are enriched. Lipid droplets are scarce. It was not possible to demonstrate histochemically catalase activity in microbodies. Dense bodies only occur in small, undifferentiated tumour cells. Multivesicular bodies, autophagosomes and residual bodies are rare. Lipofuscin is absent. Tumour cells are thought to derive from a population of undifferentiated cells ("germinative tumour cells"). Their morphological features and organelle equipment during a hypothetical course of differentiation and following dedifferentiation is described and discussed with respect to exceeding androgen synthesis.

Adenoma↗
PubMed1975

Studies on intra-arterial cushions. I. Morphology of the cushions at the origins of intercostal arteries in mice.

The origins of intercostal arteries in mice are surrounded by cushions which project into the aortal lumen. A boat-like structure, whose bow is directed against the blood stream, is formed by the cushions. The shape of this formation depends on the dilatation of the aortal wall, becoming flatter when the aortal wall is stretched. Grooves direct the blood into the initial segment of the branching artery which is narrowed in moderately distended or relaxed states of the aorta. The cushions are covered by an endothelial layer which continues to the endothelium of the aorta and of the branching artery. Ramified smooth muscle cells are found in the stroma of the cushions, while connective tissue are absent. Ramifications of the lamina elastica interna project into the stroma and faint elastic fibres reach the apical margins of the cushions. Basement membranes of ramified smooth muscle cells form a three-dimensional network which is connected with the basement membrane of the endothelium. Contacts between processes of endothelial cells and those of ramified smoot; muscle cells occur. Collagen fibrols are absent or extremely rare. In the interstitial space clusters of electron dense granules (mean diameter 500 A) are found which might be secreted by the specialized ramified smooth muscle cells. This peculiar morphology characterizes the intraaortal cushions as autonomous formations and excludes their being regarded as simple retroextension of the branching artery.

Animals↗