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M Poncelet

Publications and source records attributed to M Poncelet.

42 records · Page 3Linked to original sources

[The new versus the old antidepressant drugs: a comparative study of their psychopharmacological profiles (author's transl)].

We studied 13 known or potential antidepressants, choosen in different pharmacological classes: desipramine, imipramine, nialamide, dexamphetamine, AHR 1118, amineptine, iprindole, mianserine, nomifensine, salbutamol, TRH viloxazine, zimelidine. Each of these compounds was studied on 8 psychopharmacological tests: motor activity, reserpine induced hypothermia, reserpine induced ptosis, oxotremorine induced hypothermia, oxotremorine induced tremors, high doses apomorphine induced hypothermia, potentiation of toxic effects of yohimbine, behavioural despair. Clinical active compounds are efficient on yohimbine test and at least on one model of hypothermia; with a few exceptions, easy to explain, substances with a clearly demonstrated antidepressant activity in human have some common effects; these common effects can be used to predict, from animal experiments, an antidepressant effect in man.

Animals↗

[Models of inhibition in animal behavior].

The concept of inhibition in psychopharmacology is discussed by presenting different models of behavioral inhibition in animals. The inhibitions induced by fear or anxiety appear as a result of punishment introduction into an unknown situation, frustration... These inhibitions are particularly sensitive to minor tranquilizers. The inhibitions induced by "fatigue" appear when avoidance situations continue for 24 hours or when a situation demands a marked increase of animal activity to obtain the same reward (food). These inhibitions are particularly sensitive to psychoanaleptics. The inhibition induced by placing a animal in an inescapable situation is particularly sensitive to antidepressants.

Animals↗

[Differences in the mechanisms of the stimulant and antidepressive effects of nomifensine].

Four effects of nomifensine were studied in interaction with a dopamine receptor blocker (pimozide) and a beta-adrenergic receptor blocker (propranolol). The effects of nomifensine were divided into two categories: 1. Psychomotor stimulant effect a) Stimulation of locomotor activity in mice b) Stereotyped behavior in rats 2. Antidepressant effect a) Antagonism of hypothermia caused by reserpine in mice b) Potentiation of yohimbine-induced toxicity in mice. The psychomotor stimulant effects were antagonized by pimozide but not by propranolol. The antidepressant effects were antagonized by propranolol but not by pimozide. Our results support the hypothesis that nomifensine acts via both dopaminergic and noradrenergic mechanisms subserving distinct behavioral effects, psychomotor stimulant and antidepressant, respectively.

Animals↗

Anticonvulsant activity of diphenylhydantoin: pharmacological evidence for an alpha-adrenergic mechanism of action.

Several studies have shown that the noradrenergic system, or more precisely the alpha-adrenergic system, is implicated in the mechanism of action of DPH (Rudzik et al., 1966). In the present study we have demonstrated that prazosin, a relatively specific blocker of post-synaptic alpha-adrenergic receptors, antagonized the anticonvulsant activity of DPH on 3 models of convulsions: convulsions in the quaking mouse, convulsions induced by pentylenetetrazol, convulsions provoked by electroshock. The psychotropic properties of DPH have not been clearly demonstrated in man. It would, therefore, be of interest to perform controlled clinical studies in order to predict possible consequences of treatment in epileptics who are treated at the same time with antagonists of alpha-post-synaptic receptors.

Animals↗