PubMed Health⌕ Search

Biomedical subjects

K Unsicker

Publications and source records attributed to K Unsicker.

At least 217 records · Page 12Linked to original sources
PubMed1979

Myosin and actin containing cells in the human postnatal thymus. Ultrastructural and immunohistochemical findings in normal thymus and in myasthenia gravis.

Samples of normal human thymus of different ages (4-63 years old) were studied by immunofluorescence microscopy (using antibodies to smooth muscle myosin, to actin from the chicken gizzard, and antibodies to myosin from human striated muscle) as well as by routine electron microscopy. Thymus tissue from myasthenia gravis patients was also investigated for comparative reasons. Epithelial cells reacted with anti-smooth, but not with anti-striated muscle myosin, whereas myoid cells reacted with antibodies to striated, but not to smooth muscle myosin. Both epithelial and myoid cells displayed a strong immunoreactivity with antiactin. Corresponding to this immunoreactivity, both cell types contained bundles of thin, actin-like filaments. Myoid cells occurred in the rounded and elongated variety, and they were a normal constituent of all thymuses investigated in this study. Ultrastructurally, this non-innervated, striated muscle-like cell type possessed bundles of thin and thick filaments as well as Z lines in a rather disorganized arrangement, resembling striated muscle after denervation or various other pathologic conditions. There were no overt differences in the number and structure of myoid cells between healthy and myasthenic patients.

Acetylcholine↗
PubMed1978

Distribution of myosin and the glial fibrillary acidic protein (GFA protein) in rat spinal cord and in the human frontal cortex as revealed by immunofluorescence microscopy.

The glial fibrillary acidic (GFA) protein and myosin were localized in rat spinal cord and human frontal cortex using specific antibodies against GFA protein from human spinal cord and highly purified smooth myosin from chicken gizzard by means of an indirect immunofluorescence microscopical approach. A strong GFA protein and myosin immunoreactivity was found in astrocytes of the white and grey matter and in the external glial limitans membrane. The very fine branches of astrocytic processes stained with anti-GFA protein, but not with anti-myosin. Similar results were obtained with the human frontal cortex, where myosin antibodies failed to reveal the very fine branches of protoplasmic astrocytes. As a whole, staining with the GFA protein antiserum was more crisp than with the myosin antibody.

Animals↗
PubMed1978

Different types of small granule-containing cells and neurons in the guinea-pig adrenal medulla.

An electron microscopic, histo- and biochemical study was carried out on the adrenal medulla of newborn and adult guinea-pigs giving special emphasis to small granule-containing (SGC) cells. Adrenaline (A) was the predominating catecholamine (CA) both in newborn (70-90% of total CA) and adult (85-90%) guinea-pig adrenals. In analogy to the biochemical findings electron microscopy revealed a high predominance of A cells, which contained large granular vesicles with an average diameter of 180 nm. Most noradrenaline (NA) storing cells showed granular vesicles of a considerably smaller average diameter (80 nm) and had a higher nuclear-cytoplasmic ratio. These cells were termed SGC-NA cells. NA cells with large granular vesicles (average diameter 170 nm) were extremely rare. Another type of SGC cells contained granular vesicles with cores of low to medium electron-density (SGC-NA-negative cells). Biochemical determinations made it unlikely that these cells contained predominantly dopamine (DA). SGC cells were scarcely innervated by cholinergic nerves. They formed processes, which were found both in the adrenal cortex and medulla contacting blood vessels including sinusoid capillaries, steroid producing cells of the reticularis and fasciculata zone and processes, which were interpreted to belong to medullary nerve cells. Two types of neurons were present in the guinea-pig adrenal medulla, one resembling the principal neurons in sympathetic ganglia, the other, which, principal neurons and SGC cells. In adrenomedullary grafts under the kidney capsule, which were studied three weeks after transplantation, "ordinary" A cells resembled SGC-NA negative cells with respect to their ultramorphology. Processes of transplanted principal neurons showed uptake of 5-hydroxydopamine and, hence, were considered to be adrenergic. Despite the lack of extrinsic nerves to the transplants, few principal neurons received cholinergic synapses, the origin of which is uncertain to date.

Adrenal Medulla↗
PubMed1978

Different myosins in myoid and entodermal reticular epithelial cells of the thymus. An immunocytochemical study using specific antibodies against striated and smooth muscle myosin.

A sensitive immunofluorescence microscopical technique employing specific antibodies against highly purified actin and (smooth muscle type) myosin from chicken gizzard and myosin from human striated muscle was used to localize these contractile proteins in the thymus of rat, guinea-pig, cat and chicken. Myoid cells were seen to react with antibodies to striated, but not to smooth muscle type myosin, whereas reticular epithelial cells contained smooth, but not striated type myosin. Actin immunoreactivity was found in both myoid and reticular epithelial cells.

Actins↗
PubMed1978

Distribution of contractile proteins and adrenergic nerves in the adrenal gland of guinea-pig, rat and ox as revealed by immunofluorescence and the glyoxylic acid technique.

Myosin and actin were localized in the adrenal gland, using antibodies against these proteins which were isolated from chicken gizzard. Myosin and actin were preferentially located in vascular walls including endothelial cells and in the capsule. In rat and guinea-pig adrenal cortex, the amount of contractile elements in vascular walls corresponded well to the density of adrenergic nerves as revealed with the glyoxylic acid method.

Actins↗
PubMed1978

Nerve growth factor-induced fiber outgrowth from isolated rat adrenal chromaffin cells: impairment by glucocorticoids.

Addition of nerve growth factor to cultures of dissociated rat adrenal medullary cells caused fiber outgrowth from chromaffin cells. These fibers exhibited all the characteristics of neurites, particularly the formation of typical growth cones exhibiting intense catecholamine-specific fluorescence. Because this nerve growth factor-mediated neurite outgrowth could be abolished by physiological concentrations of glucocorticoids, it is concluded that the high glucocorticoid concentrations normally present in the adrenal medulla prevent the fiber outgrowth from medullary chromaffin cells in vivo. In dissociated sympathetic neurons the same concentrations of glucocorticoids markedly reduce but do not completely abolish neuronal fiber outgrowth.

Adrenal Medulla↗
PubMed1978

Fluorescence histochemical demonstration of a relationship between adrenergic nerves and cells containing actin and myosin in the rat ovary, with special reference to the follicle wall.

Contractile proteins (actin and myosin detected by immunohistochemistry) were present in elongated cells forming concentric layers in the theca externa of Graafian follicles and around corpora lutea. Immunofluorescent cells were also found in the ovarian stroma. Study of adrenergic nerve fibres by the glyoxylic acid technique showed numerous branches in between and in close association with the contractile cells.

Actins↗
PubMed1977

Immunofluorescence-microscopic demonstration of myosin and actin in salivary glands and exocrine pancreas of the rat.

Actin and myosin were localized in various salivary glands (parotid, submandibular, sublingual, lingual and Harderian gland) and the exocrine pancrease of rats by indirect immunofluorescence microscopy using specific rabbit antibodies against chicken gizzard myosin and actin. A bright immunofluorescent staining with both antibodies were observed at three main sites: (1) In myoepithelial cells of all salivary glands, (2) in secretory gland cells underneath the cell membrane bordering the acinar lumen (except Harderian and mucous lingual gland), and (3) in epithelial cells of the various secretory ducts (of all glands) in similar distribution as in acinar cells. The present immunohistochemical findings in acinar cells could lend further support to a concept suggesting that myosin and actin are involved in the process of transport and exocytosis of secretory granules.

Actins↗