Pharmacological and clinical studies of cyclopyrrolones: zopiclone and suriclone.

Among the non-benzodiazepine compounds which have been found to interact with the "GABA receptor-BZ receptor-chloride channel complex," the very chemically original cyclopyrrolone family has a special place. This has been demonstrated using selected pharmacological, biochemical and clinical data obtained with two cyclopyrrolones, zopiclone and suriclone, which, in addition to their capacity of displacing BZ from their sites, simultaneously possess the main pharmacological properties of BZ and well established therapeutic activities, as hypnotic and anxiolytic, respectively. However, although cyclopyrrolones recognize BZ receptor sites, their mechanism of action might not exactly fit with that of BZ.

Partial chemical characterization of cyclopyrrolones ([3H] suriclone) and benzodiazepines ([3H]flunitrazepam) binding site: differences.

Rat hippocampus membranes were treated with several protein modifying reagents (iodoacetamide, N-ethylmaleimide, tetranitromethane and N-acetylimidazole). The effects of these treatments on the binding sites of cyclopyrrolones ([3H] suriclone), a new chemical family of minor tranquilizers, and benzodiazepines ([3H] flunitrazepam) were investigated. Here we show that both ligands are similarly sensitive to cysteine alkylation: [3H] suriclone and [3H] flunitrazepam binding are reduced by iodoacetamide and slightly increased by N-ethylmaleimide.

Suriclone, a new anxiolytic of the cyclopyrrolone family: evidence for possible interference with GABAergic systems.

The action of suriclone (R.P. 31,264), a new non-benzodiazepine compound of the cyclopyrrolone family with clinical anxiolytic activity was examined using biochemical and electrophysiological models supposed to be capable of revealing central GABAergic activity.

[Relation between the inhibitory effect on the synthesis of the rabbit aorta contracting substance and prostaglandins and the anti-inflammatory activity of ketoprofen and other non-steroidal anti-inflammatory agents].

This study showed that, relative to the other antiinflammatory drugs studied, ketoprofen is a stronger inhibitor of the synthesis of prostaglandins and Rabbit aorta Contracting Substance ("RCS") by guinea pig lung tissue in vitro. Although there seems to be no close correlation between their potency as inhibitors of prostaglandin synthesis and their effectiveness as antiinflammatory agents, evaluation of both activities results in classification of the drugs in the same order.