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M Ballabio

Publications and source records attributed to M Ballabio.

49 records · Page 3Linked to original sources
PubMed1981

Determination of plasma and brain concentrations of trazodone and its metabolite, 1-m-chlorophenylpiperazine, by gas-liquid chromatography.

A sensitive and specific gas chromatographic procedure is described for the quantitation of trazodone and its active metabolite, 1-m-chlorophenylpiperazine (mCPP), in plasma and brain. After addition of internal standards, the samples were extracted with benzene and the extracts divided into two portions. One portion was evaporated to dryness, and residue dissolved in methanol and the solution injected into a gas chromatograph equipped with a nitrogen-selective detector, for trazodone quantitation. To the remaining half of the extracts, 100 microliter of heptafluorobutyric anhydride solution were added and the metabolite was measured as the heptafluorobutyryl derivative by electron-capture detection. Gas chromatography-mass spectrometry was used to confirm the specificity of the analyses. The kinetic profile of trazodone and its metabolite was investigated after oral administration of trazodone (25 mg/kg). The parent drug and its metabolite both accumulated in brain, reaching concentrations several times those in plasma. More mCPP than the parent compound entered the brain; the ratio of the area under the curve for trazodone to mCPP in plasma was about 4, whereas in brain it was only about 0.8.

Animals↗
PubMed1981

Studies on some pharmacological activities of 7-nitro-2-amino-5-phenyl-3H-1,5-benzodiazepine (CP 1414 S) in the rat. A comparison with diazepam.

Brain distribution and various pharmacological effects of 7-nitro-2-amino-5-phenyl-1,5-benzodiazepine (CP 1414 S) and diazepam were studied in rats. Injected at 10 mg/kg i.p., the compounds reached brain peak concentrations 15 min after administration and showed an apparent half-life of about 50 min. CP 1414 S was about ten times less potent than diazepam in protecting rats from pentetrazole convulsions, increasing punished responses in a "conflict" test and disrupting rotarod performance. At the lowest doses effective in these tests diazepam, but not CP 1414 S, caused significant reduction of spontaneous locomotor activity in rats. On the basis of the test selected, it is concluded that CP 1414 S causes effects similar to those shown by diazepam in the same conditions, although with less potency. It causes less depression of motor behaviour than diazepam, at least at the lowest doses and in rats.

Animals↗
PubMed1981

Antileptazol activity and kinetics of clobazam and N-desmethyl-clobazam in the guinea-pig.

The kinetic profiles and antileptazol activity of clobazam and its main metabolite were compared to assess the metabolite's contribution to the anticonvulsant activity of clobazam in the guinea-pig. The metabolite was less effective than the parent compound in terms of doses and active brain levels. However, the metabolite formed after clobazam administration accounted for the persistence of antileptazol activity in this animal species.

Animals↗
PubMed1979

Pharmacokinetics of fenfluramine enantiomers in man.

The pharmacokinetics of fenfluramine enantiomers were studied in normal volunteers following the administration of single of multiple doses of racemic fenfluramine hydrochloride. Plasma concentrations and half-lives were similar for both enantiomers after single 40 mg of 60 mg doses. However following chronic administration (2 x 40 mg for 10 days), significant differences were observed between the kinetic parameters of the two enantiomers, the l-form of fenfluramine and norfenfluramine accumulating in plasms more than the d-forms.

Adult↗
PubMedDate not supplied

Effects of increased central dopaminergic tonus on gonadotropin secretion.

Gonadotropin secretion was investigated in 10 healthy volunteers (5 men and 5 women in the early follicular phase of cycle) by the following procedures: i) infusion of saline over 4 1/2 h period; ii) infusion of dopamine (DA) 4 microgram/kg bw/min over 4 h period; iii) oral administration of L-dopa (D) 100 mg plus carbidopa (C) 35 mg after 24 h pretreatment with C 50 mg every 6 h. This last pharmacological approach selectively enhances the central dopaminergic tonus. Blood samples were withdrawn every 15 min over 4 1/2 h period. No ultradian periodicity in LH and FSH secretion was observed. No significant modification in serum FSH levels was induced by any treatment at any time, while a significant decrease in serum LH concentration was observed from 45 to 240 min during DA infusion (-46.8%; p less than 0.005) and from 60 to 240 min after D + C administration -41.5%; p less than 0.05). These data demonstrate that, in humans, acute dopaminergic stimuli have an inhibitory action on LH release and suggest that this inhibition is exerted at the central level.

Administration, Oral↗