Biomedical subjects

M Giret

Publications and source records attributed to M Giret.

11 recordsLinked to original sources

PubMed1981

On the presence of carnitine acetyl transferase in human platelets.

The presence of carnitine acetyl transferase (E.C.2.3.1.7) activity has been found for the first time in human platelets. The enzymic activity was measured by a radiometric method based on the separation of labelled acetylcarnitine and carnitine on a cation exchange column. Carnitine acetyl transferase activity closely paralleled the activity distribution of the mitochondrial marker carnitine palmitoyl-transferase. Contrary to the marker enzyme, human platelet carnitine acetyl-transferase is rather thermosensitive: 60% of its activity is lost after 10 min when kept at 37 degree C.

Acetyltransferases↗

PubMed1980

Human platelet arginase.

We report here, for the first time the presence of arginase in human platelets. This enzyme has been partially purified and some of it properties studied. Its biological significance and its involvement in polyamine biosynthesis are considered.

Arginase↗

PubMed1980

Modifications of biochemical parameters in blood platelets of schizophrenic and depressive patients.

The blood platelet may be considered as an interesting model of the serotoninergic neuron in biology and pharmacology. We studied some platelet parameters in neuropsychiatric patients (depressive and schizophrenic ones): serotonin (5-HT) uptake was abnormal for all schizophrenics and lowered for depressive patients; uptake of mepacrine, a marker of 5-HT passive diffusion, was diminished for manic patients; MAO and glutathione peroxidase activities were modified, essentially for paranoid schizophrenics and some alterations of the platelet hydroxyindole level were noticed; during treatment with neuroleptics of antidepressants biological parameters led to 'normality'. These results are discussed with clinical data and a hypothesis is proposed to join the biological modifications of paranoid schizophrenics.

Blood Platelets↗

PubMed1980

[Lysozyme content of amniotic fluid (A.F.) (author's transl)].

Lysozyme content of 47 A.F. collected at different stages of pregnancy has been measured. At the same time creatinine concentrations of 33 of those A.F. have been measured. Lysozyme content increases with the progress of the pregnancy. A similar increase is apparent when lysozyme concentration is correlated with A.F. creatinine.

Amniotic Fluid↗

PubMed1979

[The platelet model applied to the study of depressive illness (author's transl)].

The blood platelets, which serious arguments permit one to consider as valid models of serotoninergic neurones, were studied in various types of depression and during treatment with antidepressor drugs. The modifications of several platelet parameters were analysed in particular. The level of hydroxyndoles (OH-5-tryptamine or 5-HT for example) is generally lowered. The uptake of 5-HT is also reduced with normalisation by antidepressor treatments; the fixation of mepacrine, sign of the passive uptake of bioamines, is modified in the same direction, especially, in our experience, in maniacs, with a rise during treatment with phenothiazines. Finally, among the platelet enzymes, monoamine oxidase has a reduced activity in bipolar depressed patients, certain maniac depressive psychosis, and endogenic melancholias. Other platelet parameters, (liberation or release, nucleotide levels, 5-HT bonds at membrane level, etc.) may provide in the future, interesting information. In spite of sometimes contradictory data, the platelet model may be of interest, especially from pharmacological point of view.

Antidepressive Agents↗

PubMed1973