PubMed Health⌕ Search

Biomedical subjects

B Le Bourhis

Publications and source records attributed to B Le Bourhis.

At least 19 recordsLinked to original sources
PubMed1994

Factors predictive of alcohol consumption in a representative sample of French male teenagers: a five-year prospective study.

In 1985 we surveyed 691 French male teenagers aged 13-18 years. Two thirds of the same sample was again surveyed in 1990. Average consumption was 3.2 1 ethanol/year in 1985 and 7.2 in 1990. The boys who drank least in 1990 were docile, contented, religious, and already well aware of the dangers of alcohol in 1985. They smoked less, drank less coffee and went out little. The heaviest drinkers in 1990 were dissatisfied with life, unconstrained and pessimistic in 1985. They went out a lot, smoked more and drank more coffee. We intend to survey the sample again in 1995.

Adolescent↗
PubMed1994

Synaptic membrane responses to acute and chronic alcohol intoxication in high alcohol sensitive (HAS) and low alcohol sensitive (LAS) selectively bred rats.

HAS (high alcohol sensitive) and LAS (low alcohol sensitive) lines of rats have been selectively bred based on their differences in ethanol-induced sleep time. In the present study, the two lines were compared to examine another central effect of acute alcohol intoxication: namely, hypothermia. As the disturbances in membrane microorganization have been associated with the nervous system's sensitivity and tolerance to ethanol, the synaptic plasma membrane fluidity and acute sensitivity to ethanol were also evaluated by fluorescence polarization of DPH probes in the HAS and LAS rats. The two lines did not differ in the magnitude of their hypothermic response after acute injection of ethanol (3 g/kg body wt, i.p.). Although membranes in the HAS line were slightly more rigid than in the LAS line, the level of membrane disordering after acute ethanol addition was identical for the two lines in the region examined with the DPH probe. Following the chronic intoxication of the rats, the two lines developed tolerance to the hypnotic and hypothermic effects of ethanol. In the same way, a membrane resistance (i.e. tolerance) to the disordering effect of acute ethanol addition developed in the region probed with DPH. In general, the LAS line showed a more pronounced level of tolerance than the HAS line at both the functional and membrane level. These results suggest that different measures used to assess the depressant action of ethanol, such as sleep time, hypothermia or membrane disordering, may not be related and could indicate different genetic origins.(ABSTRACT TRUNCATED AT 250 WORDS)

Alcoholic Intoxication↗
PubMed1994

Tolerance and dependence in high alcohol sensitivity (HAS) and low alcohol sensitivity (LAS) rats after chronic alcohol intoxication by inhalation.

In rats selected for their differences in sleep time following acute administration of ethanol (high or low alcohol sensitivity: HAS or LAS), alcohol chronic tolerance and behavioural dependence were determined. Tolerance was assessed by calculating the interval between the loss and regain of the righting reflex following an acute administration of ethanol (4 g/kg body wt), after intoxication by inhalation of ethanol vapour for 3 weeks. The importance of behavioural dependence was estimated by measuring the ethanol intake in a free-choice situation water/ethanol (10% v/v), after intoxication by inhalation for 4 weeks. The two HAS and LAS lines did not show any behavioural dependence, while they developed a significant tolerance to the hypnotic effect of ethanol, which was more marked for the LAS line.

Administration, Inhalation↗
PubMed1991

The amount of alcohol intake and some associated factors in a representative sample of 691 French boys aged 13-18.

As a first step in a longitudinal study, we studied a sample of 691 French boys selected at random so that the region, the type of dwelling, and the profession of the wage-earner agreed with the latest official census. About 200 questions were asked by professional interviewers. The amount of alcohol intake was calculated from questions concerning type and amount of drinks consumed on all possible occasions. The mean yearly alcohol consumption was 0.91 liters of pure ethanol at 13-14 years, 2.08 at 15-16, and 5.88 at 17-18 (national average in Frenchmen 15 years and over: 16.5). Alcohol intake increases significantly with frequency of café and public dance attendance in all three age groups. Other factors, such as cigarette smoking, pop concerts or night club attendance, familial environment, show significant difference in only one or two age groups. Type of habitation, number of siblings, church attendance, etc., are not significant.

Adolescent↗
PubMed1990

[Biophysical membrane correlates of tolerance and dependence on alcohol].

A large number of studies have given clear indications that ethanol does affect the physicochemical properties of the membrane. Membrane reorganization and adaptation can develop against the acute disordering effect of ethanol during chronic intoxication. Nevertheless, there has been so far no direct evidence of correlations between functional tolerance or dependence and membrane physical states. Membrane physical state can be assessed by fluorescence polarization of DPH in the absence (measure of membrane 'fluidity') or presence (measured of membrane sensitivity) of ethanol added in vitro. Functional tolerance has been already correlated with a reduced synaptic membrane sensitivity to ethanol (membrane tolerance). Behavioural dependence was shown to be quantifiable by measurement of alcohol intake in a free choice situation (water/alcohol) solution). This dependence model allowed us to define a membrane dependence which consists in an increased membrane rigidity (or decrease in 'fluidity') persistent after withdrawal, and which was correlated to the intensity of the behavioural dependence. This biophysical expression of dependence seems rather independent of the biophysical membrane tolerance (resistance to the acute ethanol fluidizing effect), which was found to be rapidly reversible after withdrawal and re-induced by alcohol re-intake, requiring recent periods of current abuse to be expected.

Alcoholism↗
PubMed1989

Chronic toxicity/carcinogenicity study of trans-anethole in rats.

A chronic feeding study was carried out in rats with trans-anethole. The test substance was administered in the diet to groups (n = 26-78) of 312 male and 312 female Sprague-Dawley rats at concentrations of 0, 0.25, 0.5 and 1% for 117-121 wk. The average intakes of trans-anethole varied from 105-550 mg/kg body weight/day. No apparent treatment-related reactions were noted. The only effect was a transient retardation of body-weight gain. No excess mortality was caused by the treatment. No abnormalities related to treatment were seen on necropsy except for reduced adiposity in the highest dose groups. Haematological assessments did not reveal any changes related to treatment. Histological examination revealed certain non-neoplastic and neoplastic lesions common in older rats. The incidence of some hepatic lesions was significantly higher in some treated groups than in controls: altered cell foci (females of the 1% group), nodular hyperplasia (males of the 0.5% group and males and females of the 1% groups), benign tumours (females of the 1% group) and malignant tumours (females of the 1% group). The results are compared with those of previous investigations. The authors of this study stress that the low incidence of hepatocarcinomas is restricted to a single species and sex and to the highest dose tested. This pattern of species, sex and dose dependency strongly suggests that metabolic and pharmacokinetic studies will be helpful in interpreting the significance of the rat tumours with regard to the safe consumption of trans-anethole by man. The changes observed in this chronic feeding study are not thought to be of genetic origin and consequently trans-anethole does not constitute a significant carcinogenic risk to man. Further studies are in progress to substantiate this conclusion.

Allylbenzene Derivatives↗
PubMed1987

Membrane properties in behaviorally ethanol-dependent rats.

A way of quantifying alcohol behavioral dependence in rats previously developed was used in the present study to get more insight into the relations between neuronal membrane "fluidity", degree of dependence and membrane "sensitivity" (ethanol partitioning and disordering capacities).

Alcoholism↗
PubMed1987

Effect of alcohol intoxication during pregnancy on foetal and placental weight: experimental studies.

Recent animal studies have shown that alcohol intoxication in utero leads to a decrease in foetal weight and an increase in that of placenta. These findings are not, however, satisfactorily explained. The object of this study was to investigate these two effects, using inhalation of various concentrations of ethanol vapour as a method of intoxication. Three groups of 12 gravid female rats (treated groups) were intoxicated by permanent exposure to an alcohol atmosphere (19, 20 or 21 mg/l.). Three control groups of 12 gravid females were not intoxicated but had their diet reduced to the same energy intake as the treated groups. On day 21 of pregnancy, foetuses and placentas were surgically removed and individually weighed. The body-weight of foetuses was found to be lower in the treated groups than in the respective controls. Additionally the reduction of foetal weight was directly related to the severity of intoxication. Increases in placental weight were observed in the three intoxicated groups. The differences observed between foetal and placental weights may be interpreted as a foeto-protective phenomenon.

Alcoholic Intoxication↗
PubMed1986

Membrane fluidity and alcohol dependence.

Rats were chronically intoxicated with alcohol by exposing them to increasing concentrations of ethanol vapor over a 4-week period. They were tested for alcohol consumption in a free choice situation of water and 10% (v/v) alcohol. On the basis of their intakes they were divided into alcohol-dependent and nondependent groups. Synaptosome membrane fluidity evaluated by fluorescence polarization was compared between the two groups and against nonintoxicated controls. The intoxicated animals had a lower membrane fluidity than controls, mainly because of a highly significant increase of rigidity in the alcohol-dependent group. Furthermore, membrane fluidity was found to be correlated with the degree of behavioral dependence (i.e., alcohol intake during the free choice period).

Alcohol Drinking↗
PubMed1983

Alcohol exposure pattern and physical dependence.

Intoxicating animals by inhalation of ethanol vapor allows no possibility of determining accurate daily absorbed doses of ethanol. The daily BAC versus time curve may be considered as a picture of animal intoxication during the experimental period, and the area under the BAC curve (A) indicates the intoxication level of animal. On the other hand, to compensate the development of alcohol tolerance, it is necessary to gradually increase alcohol concentration in the atmosphere (ACA). A protocol was developed to study the withdrawal syndrome intensity (WSI) in rats, based on observations of behavioral alterations. Five successive grades were described and noted in relation to more and more serious WSI. Male rats were intoxicated in various protocols in which the length of alcohol exposure (7-35 days) and the rate of increase in ACA (0.22-0.70 mg/l/day) were changed. In the condition of constant increases of ACA (0.33 mg/l/day in average), WSI varied in relation to the length to alcohol exposure. When A was kept constant, the higher the ACA increase rate was, the higher the WSI was. These results are discussed with regard to patterns of consumption of alcoholic beverages by man.

Alcohol Withdrawal Delirium↗
PubMed1983

Pattern of alcohol administration and physical dependence.

The purpose of this work was to study the influence of the pattern of alcohol administration on the intensity of withdrawal syndrome. Some rats were intoxicated by inhalation of ethanol vapor. The ethanol concentration in atmosphere was increased throughout the whole experiment in such a manner that the blood alcohol concentration (BAC) during the experiment increased as a linear function of time. When the area under BAC curve was varied by changing the duration of alcohol administration and keeping constant the slope of BAC increase, the intensity of withdrawal syndrome increased with the duration of alcohol intoxication. When the duration of alcohol administration and the slopes of the BAC curves were varied in such a manner that the area under the BAC curves was kept constant, the severity of the withdrawal syndrome increased with the slope of the BAC curves.

Alcohol Withdrawal Delirium↗
PubMed1980

Biochemical correlates of tolerance in rodents and in Drosophila. Possible role of alcohol dehydrogenase, aldehyde dehydrogenase and superoxide dismutase.

In the rat, prolonged exposure to ethanol (ETOH) vapor induced an acquired increase in tolerance. After a single ETOH administration, the duration of recovery was decreased by 20% as compared to control animals and the rate of ETOH elimination from blood was increased by 27%. From the data obtained on liver enzymes--alcohol dehydrogenase (ADH), aldehyde dehydrogenase (ALDH) and superoxide dismutase (SOD)--it is suggested that the increased ALDH activity would be the consequence of an increased formation of the product of ETOH oxidation, the acetaldehyde. This over-production would not be accounted for by ADH. It is assumed that among others, the coupled reaction SOD-catalase would represent a possible alternate pathway. Data on Drosophila demonstrate that initial tolerance to ETOH is well correlated with ADH activity. It is suggested that ETOH metabolites (mainly acetaldehyde) would act also as determinant of this initial tolerance. The value of Drosophila as animal model for the study of behavioral and biochemical correlates of initial tolerance is discussed.

Alcohol Oxidoreductases↗
PubMed1980

Response of rat exocrine pancreas to chronic pulmonary ethanol intoxication.

Rats were intoxicated over a 32-day period by continuous exposure to an ethanol-enriched atmosphere. Under these conditions, body weights increased up to day 26 and blood ethanol levels increased to approximately 2 g/liter. Pancreatic and hepatic histologies were normal. Amylase levels and total pancreatic protein decreased, while lipase levels rose. These changes appear to be independent of the caloric balance of the diet.

Alcoholic Intoxication↗
PubMed1975

[Alcohol intoxication via the lung in rats].

1. The technique of chronic alcohol intoxication by inhalation of alcohol vapor was developed in rats. 2. The blood alcohol level value of rats staying in an alcohol-containing atmosphere increases (from 0 to 4 mg/l) in terms of the atmospheric alcohol level (from 0 to 20 mg/l). 3. The mean blood alcohol level of a group of animals maintained during 20 days in an atmosphere containing 15 mg/l of air, increases regularly during 7 days, and then decreases slowly. 4. Animals that are staying in an atmosphere with a regularly increasing alcohol level can breathe an air containing 20 mg/l of alcohol. This dose is early lethal when used in other animals from the beginning of treatment, what confirms the metabolic tolerance. 5. Withdrawal signs characterized by a central nervous system hyperexcitability are shown by animals which had a high blood alcohol level during 4 or 5 days, when they are back into the ambient atmosphere.

Animals↗