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G Roussel

Publications and source records attributed to G Roussel.

86 records · Page 5Linked to original sources
PubMed1978

Ultrastructural localization study of two Wolfgram proteins in rat brain tissue.

The ultrastructural immunohistochemical localization of Wolfgram proteins W1 and W2 is described in young rat brain tissue. The labelling by the antiserum to W1 is restricted to oligodendroglial cells and myelin sheaths. The plasma membrane of the cells as well as the polysomes are positively stained whereas the mitochondria and the nuclei are always free of labelling. Glial cell processes with definite organelles, which are involved in the myelination of neighbouring axons, are also positive to the antiserum. In the myelin sheaths, the positive staining occurs predominantly at the dense period line of the innermost and outermost lamellae. The present results add further evidence for a specific local synthesis of these Wolfgram proteins in oligodendroglial cells during myelination.

Animals↗
PubMed1978

Studies of soluble rat liver mitochondrial acid ATPases. II. Structural and immunological properties of ATPase 1.

We described previously the existence of a soluble ATPase activity in rat liver mitochondria [1]. The purification and catalytic properties have been described [2]. In a continuation of these experiments, we have studied the immunologic and structural properties of one molecular form of this enzyme : ATPase I. We have prepared the antiserum anti-ATPase I and demonstrated the purity of our enzyme preparation by immunodiffusion and immunoelectrophoresis. An immunohistochemical method also confirmed the localization of ATPase I in the soluble fraction of mitochondria. The molecular weight of ATPase I was measured by G 100 Sephadex gel filtration and was found to be 18,400; electrophoresis on polyacrylamide gels gave a value of 18,600. The pHi of ATPase I was found to be 7,2. Amino acid analysis showed high amounts of aspartic acid, glutamic acid, serine and glycine. The molecular weight calculated from the total amino acid residues was found to be 17,000. Alanine is the NH2 terminal amino acid. The peptide maps obtained after degrading ATPase I with cyanogen bromide or trypsin are in accordance with the methionine, lysine and arginine residues we found in the ATPase I molecule. ATPase I does not appear to be a glycoprotein.

Adenosine Triphosphatases↗
PubMed1977

Immunohistochemical studies of Wolfgram proteins in central nervous system of neurological mutant mice.

Immunohistochemical localization of Wolfgram proteins has been studied by the indirect immunoperoxidase technique with Wolfgram protein W1 antibodies in the nervous system of myelin deficient mutant mice: Jimpy, MSD and Quaking. In all these mutants, the myelinated fibers and the oligodendroglial cells (few in number) in the corpus callosum and the white matter of the cerebellum folium show a positive reaction to protein W1. These observations are in accordance with the immunological studies showing that the two major Wolfgram proteins, W1 and W2, of mutant mice have immunological similarities with that of the controls.

Animals↗
PubMed1977

[Implication of GABA in the spatial organization of the receptive fields of retinal ganglia cells of frogs].

An histoautoradiographic study of the Chicken and Frog retinae was made following an intravitreal injection if tritiated GABA. This amino acid was especially fixed at the amacrine and horizontal cell level. It has been suggested (Werblin, 1974) that horizontal cells might be responsible for the spatial organization of the receptive fields of retinal ganglion cells. GABA could thus be involved in bringing about of the centre-surround arrangement of the latter receptive fields. We have shown that picrotoxin, a specific GABA-antagonist, does indeed provoke marked changes in the activity of retinal ganglion cells. It provokes a decrease in the response threshold, a facilitation of spontaneous activities, and a marked increase in the receptive field area of the ON-OFF ganglion cells: from 12 at the start, it reaches 24 under the effect of picrotoxin.

Aminobutyrates↗
PubMed1976

Concentration of dopaminergic fibres in the marginal zone of the bird retina.

Nerve fibres containing dense core vesicles of 100-160 nm diameter are concentrated in a narrow zone (near the ora serrata) of the marginal retina in the pigeon and the chicken. Synaptic junctions exist between terminals containing dense core vesicles and the most marginal ganglion cells; however, numerous fibres seem to end freely near the vitreous body or even penetrate the pars plana of the ciliary body. Histofluorescence demonstrates the aminergic nature of these fibres. Determination of catecholamines with the dansylation technique reveals six times more dopamine in the marginal than in the central retina, whereas the noradrenalin level is unchanged. The dopaminergic fibres originate in neurons of the innermost zone of the inner nuclear layer. The marginal localisation of these fibres apparently excluding any visual function seems rather to indicate a possible photoreceptor system involved in neuro-endocrine regulation.

Adrenergic Fibers↗