acid-phosphatase and Glioma

Topics: Acid Phosphatase; Animals; Brain Neoplasms; Glioma; Glucuronidase; Humans; Lysosomes; Meningioma; Neoplasms, Experimental; Neuroma; Rats

In the past, we transfected C6 glioma cells with connexin43 cDNA, resulting in a significant increase in connexin43 mRNA and protein, as well as reduced proliferation and tumorigenesis. To investigate the morphological aspects of increased connexin43 expression in these cells, we have used a combination of immunocytochemistry, cytochemistry, and electron microscopy. By confocal immunofluorescence microscopy, connexin43 protein was localized to the plasma membrane of transfected cells and extensive intracellular accumulations of connexin43 were also demonstrated. Freeze fracture preparations showed large aggregates of particles typical of mature gap junction plaques in the plasma membrane of these cells. Ultrastructural immunogold labeling with anti-connexin43 serum revealed that connexin43 protein was present in gap junctions in the plasma membrane, some of which were found in proximity to clathrin-coated pits. In addition, various intracellular membranous profiles were immunoreactive for connexin43, including annular profiles, some with fuzzy coats and some associated with lysosome-like structures. Enzyme cytochemistry revealed that these annular gap junction profiles were often associated with acid phosphatase-positive lysosomes. These studies on the intracellular localization of gap junction protein in connexin43-transfected cells are consistent with the functional expression of the transfected connexin43 cDNA and provide a useful model to study the pathways of gap junction assembly and degradation.

Topics: Acid Phosphatase; Animals; Connexins; DNA, Neoplasm; Fluorescent Antibody Technique; Freeze Fracturing; Glioma; Immunohistochemistry; Intercellular Junctions; Lysosomes; Membrane Proteins; Microscopy, Electron; Microscopy, Immunoelectron; Rats; RNA, Messenger; Transfection; Tumor Cells, Cultured

A kinase-defective protein kinase C-alpha mutant is shown to be a phosphoprotein when expressed in COS-1 cells, indicating that intramolecular phosphorylation does not fully account for the phosphate content of protein kinase C-alpha. Furthermore, evidence is presented that the intermolecular phosphorylation of protein kinase C-alpha is due to an activity other than protein kinase C-alpha itself, and this phosphorylation appears to be necessary for protein kinase C-alpha activity. By contrast, the characteristic shift in apparent molecular mass consequent on phosphorylation in vivo can be accounted for by autophosphorylation, as demonstrated in vitro. The relationship between these phosphorylated protein kinase C-alpha species is discussed.

Topics: Acid Phosphatase; Animals; Cell Line; Electrophoresis, Polyacrylamide Gel; Glioma; Molecular Weight; Phosphoproteins; Phosphorylation; Protein Kinase C; Transfection

Opioid receptor activity in neuroblastoma x glioma NG108-15 hybrid cell membranes was attenuated by acid phosphatase purified by high performance liquid chromatography and devoid of protease activity. Treatment of membranes with this phosphatase decreased opioid inhibition of adenylate cyclase and this effect was potentiated by the presence of the opioid agonist during the phosphatase treatment. Phosphatase treatment did not affect the number of opioid receptors but it did alter the distribution of receptors among affinity states, by increasing the percentage of receptors in the low affinity state. The similarities between these effects and desensitization of the opioid receptor, during chronic opioid treatment, are discussed.

Topics: Acid Phosphatase; Animals; Chromatography, High Pressure Liquid; Cyclic AMP; Diprenorphine; Enkephalin, Leucine; Enkephalin, Leucine-2-Alanine; Etorphine; Glioma; Guanfacine; Guanidines; Hybrid Cells; Neuroblastoma; Phenylacetates; Receptors, Opioid

A method for isolating plasma membranes based on the ability of cultured C6-glioma cells to phagocytize inert material such as polystyrene (latex) beads is described. The beads (phi 1.1 micron) were incubated for 16 h or 5 h. After several washings and homogenization of the cells, the beads with the surrounding membranes were isolated by use of a sucrose density gradient. The membranes were analyzed morphologically and biochemically. Morphological studies by means of light- and electron microscopy confirmed the intracellular localization of the beads. Enzymatic studies revealed that the specific activity of acid phosphatase decreased with shorter incubation periods (from 268.00 +/- 38.56 U X mg protein-1 X min-1 after 16 h to 125.12 +/- 9.10 after 5 h), whereas that of Na, K-ATPase showed the opposite trend (3.63 +/- 0.41 and 4.73 +/- 0.78 mumoles phosphate X mg protein-1 X h-1, respectively), indicating a lesser contamination with lysosomes. The main advantages of this procedure for membrane studies lie in purity and definite orientation ("inside-out") of the membranes.

Topics: Acid Phosphatase; Animals; Cell Fractionation; Cell Line; Cell Membrane; Glioma; Microscopy, Electron; Microscopy, Electron, Scanning; Rats

Topics: Acid Phosphatase; Brain Neoplasms; Cerebrospinal Fluid; Female; Glioma; Glucuronidase; Humans; Lysosomes; Middle Aged

The effects of three widely used glutaraldehyde-based fixatives on cellular volume and structure have been studied utilizing TEM, SEM, time-lapse micrography during the fixation procedure, volumetry and demonstration of the lysosomal enzyme acid phosphatase. The cells used were in vitro cultivated human glia and glioma cells and suspensions of isolated rat liver parenchymal cells. The fixatives compared were the following: 2 per cent glutaraldehyde (GA) in 0.1 M Na-cacodylate-HCL buffer (cac) with 0.1 M sucrose (pH 7.2); total osmolality (T) 510 mOsmol; vehicle osmolality (V) 300 mOsm, 2 per cent GA in 0.1 M cac (pH 7.2; T = 410 mOsmol; V = 200 mOsmol) and 1.5 per cent GA in 0.067 M cac with 0.033 M sucrose (pH 7.2; T = 320 mOsmol; V = 170 mOsmol). It was found that the fixative with a vehicle osmolality of 300 mOsmol gave results which were interpreted as ideal while the two fixatives were hypotonic vehicles resulted in changes which were easily demonstrated during volumetry, time-lapse micrography, SEM and cytochemistry. However, the differences observed in the TEM were less obvious and difficult to interpret, the major alternations being changes in the configuration of the ER in the liver cells. In conclusion, our findings show that even small variations in the composition of a glutaraldehyde fixative can result in structural changes which do not correspond to the functional morphology of a living cell. Such changes make correct interpretation of micrographs difficult.

Topics: Acid Phosphatase; Aldehydes; Animals; Cell Line; Cells, Cultured; Fixatives; Glioma; Glutaral; Histocytochemistry; Humans; Liver; Microscopy, Electron; Microscopy, Electron, Scanning; Neuroglia; Rats

Topics: Acid Phosphatase; Adenosine Triphosphatases; Adult; Child, Preschool; Eye Neoplasms; Female; Glioma; Humans; Male; Melanoma; Middle Aged; Mitochondria, Muscle; Oculomotor Muscles; Retinoblastoma

Topics: Acid Phosphatase; Animals; Astrocytes; Brain Chemistry; Brain Neoplasms; Bucladesine; Glioma; Glucuronidase; Humans; Lysosomes; Neuroglia; Rats

Topics: Acid Phosphatase; Animals; Astrocytoma; Brain Neoplasms; Female; Glioma; Golgi Apparatus; Lysosomes; Macrophages; Maternal-Fetal Exchange; Neoplasms, Experimental; Neurilemmoma; Nitrosourea Compounds; Oligodendroglioma; Pregnancy; Rats; Rats, Inbred Strains

Topics: Acid Phosphatase; Animals; Brain; Brain Neoplasms; Ethylnitrosourea; Female; Glioma; Glucuronidase; Hexosaminidases; Lysosomes; Male; Methylnitrosourea; Neoplasms, Experimental; Nitrosourea Compounds; Oligodendroglioma; Pregnancy; Rats; Sulfatases

Topics: Acid Phosphatase; Animals; Astrocytoma; Brain Neoplasms; Cells, Cultured; Culture Techniques; Ependymoma; Glioblastoma; Glioma; Glucosephosphate Dehydrogenase; L-Lactate Dehydrogenase; Mice; Mice, Inbred C3H; Neoplasms, Experimental; Succinate Dehydrogenase

Topics: Acid Phosphatase; Adenosine Triphosphatases; Alkaline Phosphatase; Animals; Brain Neoplasms; Electron Transport Complex IV; Ependymoma; Esterases; Female; Glioma; Glucosephosphate Dehydrogenase; Glucuronidase; Hydrolases; L-Lactate Dehydrogenase; Maternal-Fetal Exchange; Neoplasms, Experimental; Nitrosourea Compounds; Pregnancy; Rats

Topics: Acid Phosphatase; Adolescent; Adult; Aged; Alcohol Oxidoreductases; Alkaline Phosphatase; Astrocytoma; Brain Neoplasms; Female; Glioma; Glutamate Dehydrogenase; Glycerolphosphate Dehydrogenase; Histocytochemistry; Humans; L-Lactate Dehydrogenase; Male; Middle Aged; Oligodendroglioma; Succinate Dehydrogenase

Topics: Acid Phosphatase; Autolysis; Brain Neoplasms; Culture Techniques; Glioma; Histocytochemistry; Humans; L-Lactate Dehydrogenase; Succinate Dehydrogenase; Time Factors

Topics: Acid Phosphatase; Animals; Brain Neoplasms; Glioma; Glucuronidase; Hexosaminidases; Humans; Hydrolases; Lysosomes; Neoplasms, Experimental; Neurilemmoma; Nitrosourea Compounds; Rats

Topics: Acid Phosphatase; Animals; Electron Transport Complex IV; Glioma; Glucuronidase; Glycoside Hydrolases; Neoplasms, Experimental; Neoplasms, Nerve Tissue; Neurilemmoma; Nitrosamines; Rats; Sulfatases

Topics: Acid Phosphatase; Alkaline Phosphatase; Animals; Brain Neoplasms; Disease Models, Animal; Enzymes; Esterases; Glioma; Glucuronidase; Histocytochemistry; Neoplasms, Experimental; Neurilemmoma; Nitroso Compounds; Oligodendroglioma; Rats

Topics: Acid Phosphatase; Alkaline Phosphatase; Aminopeptidases; Animals; Astrocytoma; Brain Neoplasms; Ependymoma; Esterases; Glioma; Histocytochemistry; Methylcholanthrene; Mice; Oligodendroglioma

Topics: Acid Phosphatase; Adenocarcinoma, Papillary; Alanine; Alkaline Phosphatase; Amides; Amidohydrolases; Arginine; Brain; Carcinoma, Intraductal, Noninfiltrating; Cecal Neoplasms; Cobalt; Dipeptidases; Female; Glioma; Humans; Leucine; Manganese; Naphthalenes; Ovarian Neoplasms; Peptide Hydrolases; Phenylalanine

Topics: Acid Phosphatase; Brain Neoplasms; Culture Techniques; Fibroblasts; Glioma; Histocytochemistry; Humans; Neuroglia

Topics: Acid Phosphatase; Adenosine Triphosphatases; Alkaline Phosphatase; Astrocytoma; Brain Neoplasms; Carcinoma; Ependymoma; Esterases; Glioma; Glucosyltransferases; Histocytochemistry; Humans; Meningioma; Neurilemmoma; Oligodendroglioma; Sarcoma

Topics: Acid Phosphatase; Alkaline Phosphatase; Brain; Brain Neoplasms; Carcinoma; Cerebrospinal Fluid; Clinical Enzyme Tests; Cyst Fluid; Geriatrics; Glioma; Glucose; Glucose-6-Phosphate Isomerase; Humans; L-Lactate Dehydrogenase; Neoplasm Metastasis; Neoplasms; Phosphates

Topics: Acid Phosphatase; Adenoma; Brain Abscess; Brain Neoplasms; Cerebral Cortex; Ependymoma; Glioma; Histocytochemistry; Humans; Lymphoma, Large B-Cell, Diffuse; Medulloblastoma; Meningioma; Microscopy, Fluorescence; Pituitary Neoplasms; Staining and Labeling

Topics: Acid Phosphatase; Alkaline Phosphatase; Astrocytoma; Brain; Brain Neoplasms; Esterases; Glioblastoma; Glioma; NAD; NADP; Neurochemistry; Oligodendroglioma; Oxidoreductases

Topics: Acid Phosphatase; Alkaline Phosphatase; Aminopeptidases; Brain Neoplasms; Esterases; Glioma; Glycosaminoglycans; Histocytochemistry; Hydrolases; Pathology

Topics: Acid Phosphatase; Alkaline Phosphatase; Aminopeptidases; Brain; Cerebellar Neoplasms; Esterases; Glioma; Medulloblastoma; Meningeal Neoplasms; Meningioma; Neoplasms, Nerve Tissue; Neurochemistry; Neurofibroma