Plasma fluphenazine levels measured by high-performance liquid chromatography in patients treated with depot injections.

Fluphenazine (CAS 69-23-8) concentrations in plasma of schizophrenic patients after oral (fluphenazine hydrochloride, Moditen) or intramuscular (fluphenazine enanthate, Moditen Retard, or fluphenazine decanoate, Modecate) administration of drug were measured by means of high-performance liquid chromatography. The extracted compound was identified by gas chromatography with mass selective detector. Pharmacokinetics of fluphenazine has been studied.

Determination of naphazoline in rat plasma using column liquid chromatography with ultraviolet detection.

A sensitive (1 ng/mL) and rapid method for the determination of naphazoline in rat plasma is described. Following extraction, the compound is analysed by reversed phase high performance liquid chromatography and ultraviolet detection at 214 nm.

Pharmacokinetic studies of ambenonium chloride in patients with myasthenia gravis.

Serum levels of ambenonium chloride (AC) were monitored in 4 myasthenic patients. This determination revealed important intraindividual variations (up to 10-fold) over a period of 24 h. Levels varied considerably between different patients (maximum serum concentration of ambenonium chloride ranged from 0.129 to 0.812 micrograms/ml) and no correlation between the daily dose and the AUC was found. These characteristic properties of ambenonium chloride could explain the erratic pattern of bioavailability observed as well as the difficulty in controlling the disease in some patients.

Ethanol intake and 3H-serotonin uptake I: A study in Fawn-Hooded rats.

Ethanol intake and synaptosomal 3H-serotonin uptake were studied in male Fawn-Hooded and Sprague-Dawley rats. Fawn-Hooded rats consumed more alcohol and more water than Sprague-Dawley rats. Plasma alcohol levels of Sprague-Dawley rats were not detectable but were about 5 mg/dl in Fawn-Hooded rats. Ethanol intake increased the Vmax of serotonin uptake in Fawn-Hooded rats in hippocampus and cortex, but not in thalamus. In Fawn-Hooded rats, serotonin uptake (Vmax) was higher than in Sprague-Dawley rats cortex. Ethanol intake reduced the Vmax of serotonin uptake in Fawn-Hooded rats in hippocampus and cortex. In cortex, the carrier affinity for serotonin was increased in alcoholized Fawn-Hooded rats. These results indicate that synaptosomal 3H-serotonin uptake is affected by ethanol intake. In Fawn-Hooded rats, high ethanol consumption is associated with high serotonin uptake. In rats presenting high serotonin uptake, alcoholisation reduces 3H-serotonin internalisation in synaptosomes, indicating a specific sensitivity to alcohol intake of serotonin uptake system.

Ethanol intake and 3H-serotonin uptake. II: A study in alcoholic patients using platelets 3H-paroxetine binding.

The kinetic parameters of 3H-paroxetine binding and 3H-serotonin uptake were studied in platelets of alcoholic patients. There was no difference between alcoholic and non alcoholic subjects in 3H-paroxetine binding. When binding and 3H-serotonin uptake were studied, in the same plasma of the same subjects, the Vmax of serotonin uptake was increased in alcoholics. The data confirm the involvement of serotonin uptake system in alcohol dependence and suggest that serotonin uptake and paroxetine binding sites may be regulated independently in this pathology.

Application of an analytical method to calcium acetylhomotaurinate determination in urine.

After urine purification, plasma and urine concentrations of calcium acetylhomotaurinate (Acamprosate, CaAOTA) were determined with a high-performance liquid chromatography method following i.v. administration of the drug in two dogs. Results obtained in serum were in good agreement with those found previously. The CaAOTA urine determination is a promising method to be used in healthy volunteers.

Pharmacokinetics of ambenonium chloride in dogs after intravenous and oral administration.

Plasma concentrations of ambenonium chloride (Mytélase) were studied, using a high pressure liquid chromatographic technique, in 11 dogs, after intravenous or oral administration of the drug. The results found suggest a complex multi-compartment storage with several periodical releases in general circulation.

Physicochemical, pharmacological and pharmacokinetic study of a new GABAergic compound, calcium acetylhomotaurinate.

It has been shown that calcium acetylhomotaurinate (Ca AOTA; Meram Patent, France) decreased voluntary ethanol intake in rats (1); this was antagonized by bicuculline. Homotaurine did not have this effect. We thought this was due to a different blood-brain barrier crossing ability for the two drugs. The present study was, therefore, planned to confirm blood-barrier crossing by Ca AOTA and to study the drug's physicochemical and pharmacokinetic characteristics. Both in vitro and in vivo (i.p.) administration of Ca AOTA increased the accumulation of [3H] GABA in rat striatal synaptosomal preparations. The chemical study confirmed Ca AOTA's great stability in biological and hydrophilic media, excluding a "homotaurine-dispensing" effect. The molecule was totally dissociated in such media, but the absence of any detectable acid form at any pH indicates that ion pairs are formed to cross barriers, and/or that a carrier system is used. The pharmacokinetic study showed short half-lives (5 and 30 min for the distribution and elimination phases) and small distribution volumes. However, the elimination phase distribution volume was dose-dependent, a further argument for a carrier transport system. From the present study it appears that Ca AOTA is an extremely stable drug, totally dissociated in hydrophilic media, which acts centrally as a GABA agonist after crossing the blood-brain barrier. It is not a precursor of homotaurine and presumably crosses barriers with the help of a transporter.

[Diffusion of vancomycin in the cerebrospinal fluid, in the dog, in the absence of meningeal inflammation]. / Diffusion de la vancomycine dans le liquide céphalo-rachidien, chez le chien, en l'absence d'inflammation méningée.

The diffusion of vancomycin into the cerebro-spinal fluid was studied in 5 healthy dogs. Its appears that vancomycin does diffuse across the blood-brain barrier. Though the concentrations reached in the CSF are low, they are of the same order of magnitude as the minimal inhibitory concentrations of this antibiotic towards the germs usually treated. The usual pharmacokinetic parameters were determined.

Complexation of the fungal metabolite tenuazonic acid with copper (II), iron (III), nickel (II), and magnesium (II) ions.

Tenuazonic acid (TA) is a phytotoxin produced by a fungal pathogen of rice, Pyricularia oryzae. We have synthesized and characterized the metal complexes of TA with copper (II), iron (III), nickel (II), and magnesium (II). The stoichiometry of the complexes determined by microanalysis and mass spectroscopy (D/CI) are Cu(II)TA2, Fe(III)TA3, Ni(II)TA2, and Mg(TA)2. Voltammograms of Fe(III)TA3, and Cu(II)TA2 in methanolic solutions confirmed this stoichiometry. Ni(II)TA2 paramagnetism and visible absorption data suggest an octahedral geometry. Fe(III)TA3 showed a characteristic visible absorption at 450 nm. Addition of Fe(III)Cl3 and Mg(II)Cl2 did not reverse the toxicity of NaTA to rice and bacterial cells, showing that this toxicity is not due to the privation of the cells of these metals essential for cell growth.

[Not Available]. / Dosage de derives de l'acide phenylpropionique A activite pharmacologique par titrage coulometrique.

Generation of ethoxide and hydroxide ions in aqueous ethanolic medium by controlled-current electrolysis is suggested for coulometric titration of 2-phenylpropionic acid derivatives. The electroreduction of the carboxylic hydrogen atom leads to the anion by elimination of a hydrogen radical. Potentiometric or conductimetric methods can be used for detection of the end-point.

[Not Available]. / Formation d'un chelate cuivre-vancomycine: application au dosage de l'antibiotique en flux continu et detection amperometrique.

The formation of a metal-complex of copper(II) with vancomycin, an antibiotic active towards Gram-positive bacteria, has been proved by spectrophotometric, polarographic and potentiometric methods. In particular, the half-wave reduction potentials and voltamperograms indicate the stoichiometry of the addition compound and the equilibrium constant. This complex has been used for determination of vancomycin by a continuous flow method with copper(II) and amperometric detection in a polarographic cell of thin-layer type.

[Not Available]. / Comportement electrochimique des antiimflammatoires derives de la pyrazolone: Application au dosage dans les medicaments.

The electrochemical behaviour of some pyrazolone derivatives has been studied in aqueous and ethanolic media. beta-Diketone compounds with a labile hydrogen atom on carbon atom 4 are directly reducible in neutral ethanol; phenazone derivatives have to be diazotized. Pulse polarography is suggested for determination of these derivatives in pharmaceutical preparations.

Etude du pouvoir oxydant de quelques periodates de tetraalkylammonium en milieu non aqueux.

The reactivity of some tetraalkylammonium periodates in periodate oxidation has been studied by electrochemistry in non-aqueous media. Conductimetric and spectrometric investigations suggest the existence of different forms of periodate, depending on the concentration and on the properties of the solvents. A study of the relation between structure and reactivity is introduced.