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F Clostre

Publications and source records attributed to F Clostre.

66 records · Page 4Linked to original sources

[Protective effects of a Ginkgo biloba extract (EGb 761) on ischemia-reperfusion injury].

EGb 761 is a standardized extract of dried leaves of Ginkgo biloba. EGb 761 is a neuroprotective and anti-ischaemic drug. Its broad spectrum of pharmacological activities allows it to be adequate to the numerous pathological requirements--haemodynamic, haemorrheological, metabolic--which occur in cerebral, retinal, cochleovestibular, cardiac or peripheral ischaemia. Moreover, EGb 761 has direct effects in retinal and myocardial ischaemia and reperfusion injuries. EGb 761 improves retinal microcirculation, reduces oedema of the retinal inner layer and protects chemoreceptors against free-radical injuries. On myocardial ischaemia-reperfusion models, EGb 761 improves myocardial functional recovery, and reduces the number of ventricular extrasytoles and the duration of ventricular tachycardia induced by reperfusion. EGb 761 protects the retina and the heart against ischaemia-reperfusion damage via its free radical-scavenging and anti-lipoperoxidative properties and its regulation of mitochondrial respiratory function.

Animals↗

[Comparative effects of an extract of Ginkgo biloba and chlorpromazine on the in vitro osmotic fragility of rat erythrocytes (author's transl)].

The effects of different concentrations of an extract of Ginkgo biloba (Gb) and of chlorpromazine (CPZ) on the osmotic lysis of rat erythrocytes (produced by dilution of the incubation medium by 30%-70%) were compared in vitro. The erythrocytes were incubated together with Gb or Cpz at the time of the hemolytic reaction at 25 degrees or 37 degrees C in either a simple phosphate buffer or in a more complete buffer containing inorganic salts at physiological concentrations. CPZ produced a dose-dependent increase in the membrane resistance, the maximum effect occurring at 10(-4) M regardless of the experimental conditions used. Gb also increased membrane resistance, but to a lesser extent than CPZ. In addition, Gb was more effective under conditions which increased erythrocyte membrane fragility; i.e., 37 degrees C, simple phosphate buffer. The mechanism of action of Gb seems to differ from that of CPZ. The activity of CPZ (as a membrane stabilizer) is, in part, due to its penetration into the membrane phospholipid layer. Gb might act in a similar manner, but could also modify Na+ transport across the cell membrane by an action on adrenergic receptors, or could stimulate Na+, K+-ATP-ase activity, as has been described for norepinephrine. As Gb contains many molecular constituents: its action on the membrane is likely to be quite complex; but this effect could be associate with its vascular therapeutic action.

Chlorpromazine↗