Michel Geffard

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Dopamine was coupled to bovine serum albumin (BSA) with glutaraldehyde, precautions were taken in order to preserve the catechol ring. After injection of this immunogen into rabbits, anti-dopamine antibodies were obtained and tested using radioimmunochemical binding studies and adsorption to catecholamine covered sepharose beads. A good correlation was(More)
The aim of the present study is to examine whether serotonergic terminals of the rat brain are induced to contain dopamine by L-DOPA administration. In rats that received intraperitoneally L-DOPA plus a peripheral decarboxylase inhibitor, we showed by use of a double-labeling immunofluorescence method that dopamine was localized in serotonergic fibers of(More)
We have quantified the density of serotonin axonal varicosities, their synaptic incidence and their distribution among potential targets in the pars reticulata and pars compacta of the rat substantia nigra. Serotonin axonal varicosities, counted at the light microscopic level following in vitro [3H]serotonin uptake and autoradiography, amounted to 9 x(More)
The existence of GABAergic neurons in the rat suprachiasmatic nucleus (SCN) was demonstrated by three specific markers; mRNA coding for glutamic acid decarboxylase (GAD) and visualized by in situ hybridization using a 35S-labelled cDNA probe, and GAD protein and GABA were identified by immunocytochemistry using specific antisera. In situ hybridization(More)
Antibodies against gamma-aminobutyric acid (GABA)-glutaraldehyde-lysine were obtained by using a procedure based upon (i) a high yield of coupling of GABA to protein carriers, (ii) the reduction of the resulting immunoreactive double bonds, and (iii) a protocol of alternative immunizations using different immunogens having in common only the(More)
Peroxidase-antiperoxidase electron microscope immunocytochemistry with an antiserum against noradrenaline-glutaraldehyde-protein conjugate was used to identify cortical noradrenaline terminals (axonal varicosities) from the upper layers of the frontal, parietal and occipital cortex in adult rat. A large number of immunostained varicosities were examined in(More)
Immunohistochemical analysis documented the presence of gamma-aminobutyric acid (GABA)-containing fibers and GABA-containing chromaffin cells in canine adrenal glands. A dense network of fibers was visualized at the boundary between medullary and cortical cells, and, in the medullary tissue, GABA-containing fibers surrounded chromaffin cells. Some of these(More)
The development of 5-hydroxytryptamine (5-HT) innervation in the spinal cord was studied from embryonic day 14 (E14) to adulthood. Sprague-Dawley rats were fixed by perfusion with 5% glutaraldehyde in cacodylate-sodium metabisulfite buffer, and vibratome sections were processed for immunocytochemistry with a 5-HT antiserum. For electron microscopy, the(More)
Using an immunoperoxidase technique, we have localized by light and electron microscopy GABA-immunostained fibers within a component of the efferent innervation of the organ of Corti. At the light microscopic level, GABA-immunostained fibers were observed within the inner spiral bundle (below the inner hair cells) and the tunnel spiral bundle. The(More)
Dopamine (DA)-containing projections to the cerebral cortex are considered to play an important role in cognitive processes. Using a recently developed monoclonal antiserum directed against DA and an antibody directed against tyrosine hydroxylase in combination with Golgi impregnation and electron microscopy, we have observed that DA and tyrosine(More)