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D Dahl

Publications and source records attributed to D Dahl.

At least 163 records · Page 9Linked to original sources
PubMed1983

Laminin is produced by early rat astrocytes in primary culture.

The production of laminin by early rat astrocytes in primary culture was investigated by double immunofluorescence staining for laminin and the glial fibrillary acidic protein (GFAP), a defined astrocyte marker. In early cultures (3 d in vitro; 3 DIV) cytoplasmic laminin was detected in all the GFAP-positive cells which formed the major population (80%) of the nonneuronal cells present in cultures from 20-21-d embryonic, newborn, or 5-d-old rat brains. Monensin treatment (10 microM, 4 h) resulted in accumulation of laminin in the Golgi region, located using labeled wheat germ agglutinin. Laminin started gradually to disappear from the cells with the time in culture, was absent in star-shaped, apparently mature astrocytes, but remained as pericellular matrix deposits. The disappearance of cellular laminin was dependent on the age of the animal and the time in culture so that it started earlier in cultures from 5-d-old rat brains (5 DIV) and approximately following the in vivo age difference in cultures from newborn (12 DIV) and embryonic (14 DIV) rat brains. Our results indicate that laminin is a protein of early astrocytes and also deposited by them in primary culture, thus suggesting a role for this glycoprotein in the development of the central nervous system.

Animals↗
PubMed1983

Neurofibrillary changes in human brain. An immunocytochemical study with a neurofilament antiserum.

Brain samples from cases of Alzheimer's disease, postencephalitic Parkinson's disease, progressive supranuclear palsy, amyotrophic lateral sclerosis, and Pick's disease, as well as from a case of Alzheimer's disease with a large number of Hirano bodies, were stained with the peroxidase-anti-peroxidase method using an antiserum previously shown to immunoreact with normal neurofilaments and neurofilament polypeptides. The specificity of this serum was confirmed by absorption an purified neurofilament proteins. Neurofibrillary tangles of Alzheimer's disease, postencephalitic Parkinson's disease, and progressive supranuclear palsy, Pick's bodies, and the fibrillary inclusions of amyotrophic lateral sclerosis were all immunostained. Hirano bodies showed no immunostaining. Thus, with the exception of the Hirano bodies, all the neuronal fibrillary inclusions examined appeared to share common antigenic characteristics. The orgin of all these structures from normal neurofilaments is postulated.

Amyotrophic Lateral Sclerosis↗
PubMed1983

Neonatal rat hypothalamus cell culture: neuron subpopulations secrete immunoreactive beta-endorphin but not immunoreactive ACTH.

Primary cultures of dissociated hypothalamic cells were prepared from 1-day-old rat neonates. Studies with cell-specific antisera revealed the presence of neurons, glial cells, oligodendrocytes and fibroblast-like cells. By immunohistochemistry, two morphologically distinct cells in culture were positive for immunoreactive beta-endorphin (IR-beta-EP). The medium derived from these cultures contained radioimmunoassayable IR-beta-EP, but not IR-ACTH. These data suggest that, in rat neonatal hypothalamic cultures, two subpopulations of cells exist which store and secrete IR-beta-EP, but not IR-ACTH.

Adrenocorticotropic Hormone↗
PubMed1983

Immunolabeling of carbonic anhydrase isoenzyme C and glial fibrillary acidic protein in paraffin-embedded tissue sections of human brain and retina.

The specificities of carbonic anhydrase isoenzyme C (CA C) and glial fibrillary acidic (GFA) protein as immunocytochemical markers for different glial cell populations in human brain and retina were studied using indirect immunofluorescence and peroxidase-antiperoxidase complex methods. With antibodies against CA C, only those cerebral cells that were morphologically oligodendrocytes and Müller cells of the retina showed positive immunostaining reaction, whereas antibodies against GFA protein selectively labeled cerebral astrocytes and a part of the glial cells and fibers in the inner layers of the retina. In double labeling, when both glial cell markers were successively localized in the same cerebral tissue sections, GFA protein immunofluorescence was never found in the immunoperoxidase-stained CA C-positive cells, which further supports the oligodendrocyte-specificity of CA C in human brain.

Brain↗
PubMed1983

Differential diagnosis of chordoma, chondroid, and ependymal tumors as aided by anti-intermediate filament antibodies.

Six chordomas, nine chondrosarcomas, and three myxopapillary ependymomas of the filum terminale were evaluated immunohistochemically for the expression of intermediate filament proteins by the use of monospecific antibodies against intermediate filament proteins of keratin, vimentin, and glial fibrillary acidic protein (GFAP) type. All chordomas were positive for keratin but negative for GFAP, whereas chondrosarcomas and ependymomas were negative for keratin. Chondrosarcomas showed strong vimentin positivity, whereas ependymomas were positive for GFAP. Chordomas showed desmosomelike junctions by electron microscopy, whereas chondrosarcomas of different types showed no junctions or only primitive ones. By electron microscopy chordomas often showed prominent intermediate filaments also associated with desmosomes, and poorly differentiated chondrosarcomas also showed prominent intermediate filaments. Keratin positivity of chordomas suggests their epithelial nature, while vimentin positivity of chondrosarcomas is in line with their mesenchymal derivation. The results also show that antibodies against different intermediate filament proteins can be applied as diagnostic aids in making the distinction between chordomas, chondroid tumors, and ependymal tumors.

Adolescent↗
PubMed1983

Expression of a neural type of intermediate filament as a distinguishing feature between oat cell carcinoma and other lung cancers.

Expression of intermediate filaments was studied immunohistologically in oat-cell (6 cases), epidermoid (9 cases), adeno- (7 cases), large-cell anaplastic (3 cases), and bronchioalveolar carcinoma (3 cases), of lung. Affinity-purified antibodies against epithelial (anti-keratin), neural (anti-neurofilament), muscle (anti-desmin) and mesenchymal (anti-vimentin) intermediate filaments were used. In indirect immunofluorescence microscopy of oat-cell carcinomas a positive cytoplasmic fluorescence was seen only with antibodies against neural intermediate filaments, neurofilaments, while no staining of the tumor cells was observed with antibodies against other types of intermediate filaments. On the other hand, all the epidermoid, adeno, anaplastic, and bronchioalveolar carcinomas showed constantly a strong reaction with anti-keratin antibodies in a varying number of cells but no decoration with anti-neurofilament antibodies. The results show that expression of neural intermediate filaments is a major distinguishing feature between oat-cell carcinomas and other lung cancers and suggest that anti-neurofilament antibodies can be used as a diagnostic aid in the surgical pathologic study of pulmonary neoplasms.

Adenocarcinoma↗
PubMed1983

Neurofilaments in adrenal and extra-adrenal pheochromocytoma. Demonstration using immunofluorescence microscopy.

Three cases of pheochromocytomas (two adrenal and one retroperitoneal) were studied immunohistologically, using specific antibodies against different types of intermediate filaments. A strong positive reaction was seen in immunofluorescence microscopy with antineurofilament antibodies, while no staining of tumor cells was observed with antikeratin, antivimentin, or antidesmin antibodies. The results are in accordance with the neuroepithelial derivation of adrenal medulla and paraganglia and suggest that antineurofilament antibodies can be used as an adjunct aid in identifying pheochromocytomas.

Adolescent↗
PubMed1982

Vimentin in the central nervous system. A study of the mesenchymal-type intermediate filament-protein in Wallerian degeneration and in postnatal rat development by two-dimensional gel electrophoresis.

Intermediate filament proteins were identified by two-dimensional gel electrophoresis in urea extracts of rat optic nerves undergoing Wallerian degeneration and in cytoskeletal preparations of rat brain and spinal cord during postnatal development. The glial fibrillary acidic (GFA) protein and vimentin were the major optic nerve proteins following Wallerian degeneration. Vimentin was a major cytoskeletal component of newborn central nervous system (CNS) and then progressively decreased until it became barely identifiable in mature brain and spinal cord. The decrease of vimentin occurred concomitantly with an increase in GFA protein. A protein with the apparent molecular weight of 61,000 and isoelectric point of 5.6 was identified in both cytoskeletal preparations of brain and spinal cord, and in urea extracts of normal optic nerves. The protein disappeared together with the polypeptides forming the neurofilament triplet in degenerated optic nerves.

Aging↗
PubMed1982

Studies on the biosynthesis of intermediate filament proteins in the rat CNS.

The biosynthesis of brain intermediate filament proteins [neurofilament proteins and glial fibrillary acidic protein (GFA)] was studied with cell-free systems containing either rat spinal cord polysomes (free polysomes or rough microsomes) and rabbit reticulocyte factors or wheat germ homogenate containing spinal cord messenger RNA. The products of translation were isolated by immunoaffinity chromatography and then analyzed by two-dimensional gel electrophoresis (2DGE) followed by fluorography. The free polysome population was found to synthesize two neurofilament proteins (MW 145K, pI 5.4, and MW 70K, pI 5.3) and three isomers of GFA (alpha, beta, and gamma) that differ in isoelectric point. Wheat germ homogenate containing messenger RNA extracted from free cord polysomes synthesized two proteins that comigrated with neurofilament protein standards at 145K 5.4 and 70K 5.3; these proteins were partially purified by neurofilament affinity chromatography. The wheat germ system also synthesized the alpha, beta, and gamma isomers of GFA as characterized by immunoaffinity chromatographic purification and comigration with standards in 2DGE analysis. Our data are consistent with the conclusion that synthesis of neurofilament proteins requires multiple messenger RNAs. Also, synthesis of intermediate filament proteins occurs in the free polysome population; detectable amounts of these proteins were not synthesized by the rough microsomes.

Animals↗
PubMed1982

Ultrastructural localization of neurofilament proteins in aluminum-induced neurofibrillary tangles and rat cerebellum by immunoperoxidase labeling.

The localization of neurofilament proteins was investigated at the light and electron microscopic levels by the peroxidase-antiperoxidase procedure in the motor neurons of rabbit spinal cord accumulating bundles of filaments (neurofibrillary tangles) consequent to the intrathecal injection of aluminum and in rat cerebellum. As indicated by immunoaffinity chromatography the antisera used in this study reacted with 72,000- and 150,000-dalton polypeptides of the mammalian neurofilament "triplet". In the motor neurons of rabbit spinal cord neurofibrillary tangles were prominently stained. Regions of cytoplasm surrounded by the tangles were negative. In the cerebellar cortex the reaction product was confined to structures containing large amounts of neurofilaments, particularly the terminal branches of basket axons surrounding Purkinje cells. The absence of staining in the outer molecular layer containing processes with other types of filaments, that is, Bergmann glia (gliofilaments) and thin parallel fibers (microtubules), served as control for the specificity of the reaction. In both spinal cord and cerebellum the reaction product appeared as elongated strands. In spinal cord, filaments cut in cross-section had the appearance of peripherally stained circular structures approximately 250 A in diameter.

Aluminum↗
PubMed1982

Glial disturbances in isolated neocortex: evidence from immunohistochemistry of intraocular grafts.

Cortex cerebri pieces from fetal donors were homologously and bilaterally grafted to the anterior eye chamber of adult albino rats. After intraocular maturation, presence of an external glial membrane, glial membranes surrounding blood vessels and cortical astrocytes was demonstrated using antisera raised against glial fibrillary acidic protein (GFA). Cortex cerebri pieces were also combined in the eye with a previously grafted locus coeruleus piece (LC). The amount of GFA-like immunoreactivity in such cortex grafts was much lower than in single cortex grafts. When compared to adult cortex cerebri in situ it was evident that the amount of GFA-like immunoreactivity in the cortex grafts combined with LC grafts was more normal than in single grafts. The difference in GFA-like immunoreactivity may be due to an increased number of astrocytes in isolated cortex grafts. Alternatively, the astrocytes in the cortex grafts combined with LC grafts are more normally matured and therefore do not stain immunohistochemically with GFA. It is concluded that the LC grafts in some way stimulate the maturation of the cortex grafts, probably by a diffusable or membrane-bound factor.

Animals↗
PubMed1982

Immunohistological localization of desmin, the muscle-type 100 A filament protein, in rat astrocytes and Müller glia.

The distribution of glial fibrillary acidic (GFA) protein and desmin was compared in cryostat sections of rat brain, spinal cord, and eye by immunofluorescence and peroxidase-antiperoxidase (PAP) staining. Desmin antisera were raised to antigen purified from chicken gizzard. In rat brain and spinal cord, GFA protein and desmin were selectively localized in astrocytes. Neurons and axons were not stained. The only difference between GFA and desmin antisera was the staining of smooth muscle in small arteries with anti-desmin. It was only in retinal glia that a difference in the localization of the two proteins was apparent. As previously reported, only the glia limitans on the inner surface of the retina was demonstrated with GFA antisera in the normal eye. With anti-desmin Müller fibers spanning the whole thickness of the retina were stained. It is concluded that GFA and desmin form two distinct systems of 100 A filaments in astroglia, as previously reported for GFA and vimentin.

Animals↗
PubMed1982

Glial fibrillary acidic (GFA) protein in Schwann cells: fact or artifact?

Antisera to the glial fibrillary acidic (GFA) protein stained a subpopulation of Schwann cells in cryostat sections of rat sciatic nerve by indirect immunofluorescence and by the peroxidase-antiperoxidase (PAP) procedure. The staining pattern was entirely different from that obtained with vimentin antisera, which uniformly decorated endoneurial tubes. Electron microscopic examination of sciatic nerve provided a possible explanation for the relatively small number of Schwann cells decorated by GFA antisera: 10 nm filaments were mainly confined to Schwann cell processes surrounding nonmyelinated axons. A marked increase in GFA-positive Schwann cells and in Schwann cells containing filaments by electron microscopy was observed in sciatic nerves undergoing Wallerian degeneration. Conversely, immunochemical procedures failed to demonstrate the presence of antigen reacting with GFA antisera in extracts of sciatic nerve, both normal and degenerated. These include absorption experiments, double immunodiffusion, immunoaffinity chromatography, and immunoradiometric assay. Two explanations may be considered for these findings: i) Schwann cell intermediate filaments and GFA protein share common antigenic determinants, the immunohistological methods being more sensitive to detect cross-reactivity as compared to immunochemical procedures on tissue extracts; and ii) the binding of anti-GFA to Schwann cell 10 nm filaments is not due to immunological cross-reactivity.

Animals↗
PubMed1982

Immunostaining of neurofibrillary tangles in Alzheimer's senile dementia with a neurofilament antiserum.

Using anti-chicken brain neurofilament antisera, Alzheimer's neurofibrillary tangles from two patients with senile dementia were stained by immunofluorescence and by the peroxidase-antiperoxidase procedure in cryostat sections of hippocampus and frontal cortex. In sections of cerebellum obtained from the same patients, the distribution of immunostaining was the same as that observed in experimental animals: Purkinje cell baskets and nerve fibers in the inner half of the molecular layer were demonstrated selectively. The immunostaining of the tangles was abolished when the antisera were absorbed by their own antigen, by bovine brain filament preparations, or by the fraction of bovine brain filament preparations nonabsorbed on anti-glial fibrillary acidic (GFA) protein immunoaffinity columns. Absorption with a bovine microtubule preparation isolated by two cycles of the assembly-disassembly procedure did not abolish the staining. Immunostaining experiments conducted on bovine brain filament preparations resolved on sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the antisera staining the tangles reacted with the 200,000-, 150,000-, and 70,000-dalton neurofilament polypeptides. Antisera raised to the 150,000- dalton bovine neurofilament polypeptide isolated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis stained the tangle much less intensely, although Purkinje cell baskets in the cerebellum appeared well stained. No staining of neurofibrillary tangles was observed with antisera to other classes of 10-nm filament proteins (GFA protein, vimentin, and desmin).

Aged↗