Publications by authors named "Guimbal C"

A family of structurally related, Na+/Cl(-)-dependent plasma-membrane transporters catalyze the uptake of several neurotransmitters, osmolytes and other metabolites into cells. Four different members of this transporter family have been cloned from mammalian sources which all transport 4-aminobutyric acid (GABA) but differ in their pharmacological profiles and in their tissue distribution. We report on the cloning, sequencing and functional expression of a transporter for GABA and beta-alanine from the electric lobe of Torpedo.

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A family of homologous, Na+/Cl- dependent plasma membrane transporters catalyze the uptake of a number of neurotransmitters and structurally related compounds into cells. Here, we report the cDNA cloning, sequencing and functional characterization of a non-mammalian member of this transporter family. A creatine transporter from the electric ray, Torpedo marmorata, displays 64% amino acid identity with its rabbit counterpart and has a similar substrate affinity and specificity.

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A cDNA has been cloned from rabbit brain that is a new member of the emerging family of Na(+)-dependent plasma membrane transporters for several neurotransmitters and structurally related compounds. Functional expression of this cDNA in COS-7 cells identifies its product as a Na(+)- and Cl(-)-dependent creatine transporter with a Km of approximately 35 microM. Its creatine transporter activity is efficiently antagonized by 3-guanidinopropionate, a well characterized alternative substrate of creatine transport in several tissues, and by 4-guanidinobutyrate.

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Iodobenzamide is a promising agent to investigate D2 receptors by SPECT in living human brain. In this work, we have evaluated this radiolabeled compound in two animal models of D2 receptors supersensitivity. In the first model, rats were treated chronically with haloperidol during three weeks (S.

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We synthesized a new spiperone derivative: iodoethylspiperone (IES) to perform dopamine D2 receptor exploration by SPECT. IES was prepared from a precursor: tosylethylspiperone, and characterized by i.r.

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The detection of psychopharmacological properties of 8 synthetic substances derived from barbituric didn't allow to consider the existence of well characterised psychotropic properties, particularly hypnotical, but only antalgic and sedative effects (or stimulating activity very low). If the presence of a benzyl substituent can confer an affinity for the nervous central system superior to the one developed when an allyl rest is in the same position, the presence of an OH or OCH3 in other place inverse the sedative character in stimulant potentiality.

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