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P Simon

Publications and source records attributed to P Simon.

At least 523 records · Page 29Linked to original sources

[Effects of four beta-blocking agents on some psychopharmacological tests in mice (author's transl)].

Common effects of four beta-adrenergic blocking drugs have been investigated in mice using classical and new psychopharmacological tests. Propranolol, alprenolol, practolol and penbutolol reduced the increase in locomotor activity produced by reserpine after MAO inhibition; they produce hypothermia when associated with amphetamine and they increase oxotremorine-induced hypothermia. Regarding these three tests the studied substances ranged themseleves in the same order of potency: penbutolol greater than propranolol greater than alprenolol greater than practolol. Propranolol and penbutolol decreased the toxicity provoked in crowded mice by amphetamine or by the association pargyline-reserpine; alprenolol and practolol did not. Propranolol, penbutolol and alprenolol antagonized the amphetamine-induced increase in motor activity; practolol did not. When used at doses for which d-l propranolol was active, the dextrogyre isomer of propranolol was without effect whatever the test studied. It is suggested that for the selection of a beta-blocking drug, regarding central effects in man, the tests described would deserve consideration.

Adrenergic beta-Antagonists↗

An iron-containing superoxide dismutase from Anacystis nidulans.

Superoxide dismutase (SOD) was isolated and purified from Anacystis nidulans to near electrophoretic homogeneity. The enzyme has a molecular weight of 37,500, as determined by gel filtration and SDS-gel electrophoresis. The enzyme molecule consists of two subunits of identical molecular weight. Proton-induced X-ray elemental analysis (PIXE) showed that the SOD of A. nidulans is an iron-containing enzyme; the Fe:enzyme mol ratio was found to be 1. The EPR spectra indicated that the active center contains high-spin ferric ion. Based on quantitative EPR data, we conclude that eseentially all iron ions were detected in the EPR experiments and were present in the Fe3+ active center. Effective g'-values were calculated from computer-simulated spectra and analysis of the g'-value anisotropy of the +/-3/2 Kramers doublet made the calculation of crystal field parameters possible. The symmetry of the Fe3+ ion in the SOD molecule was found to be close to rhombic (E/D=0.240).

Binding Sites↗

Amoxapine in experimental psychopharmacology: a neuroleptic or an antidepressant?

2-Chloro-11-(piperazinyl)dibenz[b,f][1,4]-oxazepine (amoxapine) gives an unusual spectrum in psychopharmacological tests. Many of its effects are similar to those of neuroleptics: sedation, decrease in motor activity, catalepsy (which is, however, qualitatively different from that induced by classical neuroleptics), transitory suppression of avoidance reaction, antagonism of amphetamine induced toxicity in crowded mice and inhibition of stereotyped behavior induced by amphetamine in rats, and antagonism to various effects of apomorphine (stereotyped behaviour in rats, climbing behaviour, stereotyped behaviour and hypothermia in mice). At similar doses which produce the above mentioned effects, amoxapine also shows effects atypical for a neuroleptic, but which are relatively characteristic of antidepressants: antagonism of prochlorperazine-induced catalepsy in rats, inhibition of reserpine induced hypothermia in mice and enhancement of yohimbine toxicity in mice. The profile of this substance does not facilitate the anticipation of therapeutic effects in humans.

Amoxapine↗

[The role of norepinephrine in affective disorders (author's transl)].

The role of norepinephrine in affective disorders is supported by the following data. There is a decrease of activity of the noradrenergic system in depressive patients, evaluated by: --a decrease of the metabolism of noradrenaline; --an hyperreactivity of adrenergic receptors; --a decrease of the secretion of some hormones (melatonine, renine, corticosteroides) the liberation of which is mediated by stimulation of adrenoreceptors. The well recognized antidepressant drugs are able to activate by different mechanisms the noradrenergic system. Reciprocally, drugs well known to stimulate noradrenergic system are able to increase mood. Complementarily, antimaniac drugs are adrenolytic and adrenolytic drugs are antimaniac and depressogenic.

Antidepressive Agents↗

[Interest and limits of estimation of the carcinoembryonic antigen in colonic and rectal (author's transl)].

An attempt is made to define the usefulness and limitations of carcinoembryonic antigen (CEA) radioimmunoassay for evaluation of diagnosis, tumor resection and detection of tumor relapse in 108 patients with colorectal carcinoma. Preoperative CEA levels were correlated with pathological stage and tumors localisations. Increasing levels of CEA were found with advanced stage of disease (Stage C and D lesions). Our results indicate: 1) that an incomplete drop in circulating CEA level one month after surgery was a bad prognostic sign; 2) that relapses of colon and rectum carcinoma can be detected by increased CEA levels months before the appearance of any clinical evidence.

Carcinoembryonic Antigen↗

Pharmacokinetics of perhexiline maleate in anginal patients with and without peripheral neuropathy.

Perhexiline maleate (Pexid) which has been in general use in France with good results for the treatment of angina pectoris since 1973, may be associated with severe side effects including peripheral neuropathy. The present study is a comparison of the pharmacokinetics of perhexiline maleate in anginal patients with and without signs of peripheral neuropathy. Compared to the latter, those with neuropathy had higher plasma levels of perhexiline, slower hepatic metabolism and a longer plasma half-life. Thus, peripheral neuropathy associated with perhexiline maleate treatment appears to be a direct toxic effect due to accumulation of the drug. The accumulation might result either from a decreased volume of distribution secondary to a loss of body weight, possibly drug-induced, or to slow hepatic metabolism of perhexiline of genetic origin or due to hepatic disease, possibly drug-induced. The neuropathy is rarely an isolated event, as it is often associated with one or more adverse effects of perhexiline.

Aged↗

[B virus chronic hepatitis in the haemodialysed uraemic patient. Correlation between hepatic lesions and the presence of antigen e in 12 patients (author's transl)].

Twelve patients on haemodialysis for 6 months to 3 years contracted AgHBs positive hepatitis, 9 being also Ag e positive. They continued to carry the same antigens. Histological surveillance was begun from the 6th month of the disease onwards, with 2 to 4 repeated biopsies in 1,5 to 3,5 years in 9 patients, the last 3 having only one biopsy between the 8th and the 15th month. In 6 patients, the first biopsy revealed chronic persistent hepatitis (CPH) and in other 6 (5 male and 1 female) chronic aggressive hepatitis (CAH). Subsequent biopsies revealed cirrhosis in a patient treated with alphamethyldopa (Ag e +), the absence of any changes in 7 other patients (4 CPH including 3 Ag e + and 3 CAH including 2 Ag e +), and an improvement in the last. Long term surveillance of hepatitis B by repeated biopsies in haemodialysed patients reveals that histological lesions are stable at 2 years, that certain drugs may have an aggravating role and that Ag e has no prognostic value.

Biopsy, Needle↗

Benzodiazepines and behavioral effects of reward (water) omission in the rat.

Two behaviors related to nonreward (omission of water in an enclosure where the rats were habituated to drink) were studied. The time spent licking the bottles during water omission and the time spent drinking during a subsequent 5-min drinking session (water available) were recorded. The drinking session was performed 30 min after the water-omission session. Rats subjected to water omission showed an enhanced drinking time that varied with the length of the water omission session, with the motivational state of the animals, and with the previous number of water-omission sessions. Diazepam, chlordiazepoxide, lorazepam, and meprobamate (i.p., 30 min before water omission), increased the time spent licking the empty bottles, but failed to abolish subsequently enhanced drinking. However, some of our data suggested that minor tranquilizers weakly reduced the increased drinking induced by nonreward, despite their direct stimulation on water drinking. It is proposed that either minor tranquilizers are devoid of general antifrustration activity or nonreward-induced frustration and nonreward-induced drive enhancement may not be correlated.

Amobarbital↗

Benzamides and classical neuroleptics: comparison of their actions using 6 apomorphine-induced effects.

The effects of 6 benzamides and 8 classical neuroleptics were studied on 6 different apomorphine-induced effects. These drugs did not antagonize all the effects in the same way. The differences are discussed according to the two types of dopaminergic receptor hypothesis. Some apomorphine-induced effects (stereotyped behavior, circling behavior, climbing behavior, and increased motor activity) could be related to stimulation of one type of dopaminergic receptor, other effects (hypothermia and decreased activity) to the other type. Pimozide, sulpiride, thioproperazine, GRI 1665 and TER 1546, could block selectively one type of dopaminergic receptor, at least in a given range of doses. Clozapine, chlorpromazine, levomepromazine, and thioridazine, could block selectively the other type of dopaminergic receptor. Haloperidol, metoclopramide, prochlorperazine, sultopride, and tiapride, could block both types of dopaminergic receptors with equal intensity whatever the dose.

Animals↗