PubMed Health⌕ Search

Biomedical subjects

G Laborit

Publications and source records attributed to G Laborit.

At least 19 recordsLinked to original sources
PubMed1992

Variations of lipid profile in animals caused by adenosine analogs: N6 (amido-3-propyl) adenosine hydrochloride and (carboxamido-3-propylamino)-6-(triproprionyl) 2',3',5'beta (D-ribosyl)-9-purine.

N6-substituted adenosine analogues are powerful inhibitors of lipolysis in the adipose tissues of animals and humans, because of their agonist effect on A1 purine receptors. Using a model of hypertriglyceridemia provoked by intravenous injection of Triton WR 1339, we observed that Agr 529 [N6(amido-3-propyl)adenosine hydrochloride] at 2 mg.kg-1 intravenous in rabbits, and intraperitoneally and orally in rats led to a return of the levels of circulating triglycerides to normal values. In addition, Agr 529 and its prodrug, Agr 540 [(carboxamido-3-propylamino)-6-(triproprionyl)2', 3',5'beta(D-ribosyl)-9-purine] administered to rats at 3 and 30 mg.kg-1, respectively, returned plasma triglyceride concentrations to normal levels. Intravenous administration of Agr 529 to normal rats led to decreased concentrations of plasma fatty acids, phospholipids, triglycerides and total cholesterol as a function of dose. The decrease began at 0.1 mg.kg-1 and was highly significant at 3 mg.kg-1. In the same conditions, the intraperitoneal administration of Agr 529 caused a dose-dependent hypolipemia. There was no apparent effect on cholesterol and on the triglycerides of high density lipoproteins. A kinetic study showed that the antilipemic effect of Agr 529 intravenously injected at 3 mg.kg-1 began 30 minutes after the injection with a maximum effect at 2 hours. The effect persisted up to 8 hours after injection. The present results show that the administration of Agr 529 and Agr 540 to normal animals causes hypolipemia (decrease in fatty acids, phospholipids, triglycerides and cholesterol) and restores induced hypertriglyceridemia. These effects may be attributed to an interaction of the molecules with A1 purinergic receptors of adipose tissue.

Adenosine↗
PubMed1979

[The Cerebral Function Monitor. Description, functioning and interpretation principles].

The Monitor of Cerebral Function enables continuous monitoring of the cerebral electrical activity and this over long periods due to the slow recording speeds. The cerebral electrical signals picked up by the electrodes attached to the scalp are registered in the form of a curve which fluctuates to a greater or lesser extent depending on the recording speed. The examination of the height of the curve with respect to zero and its amplitude indicates the voltage of the cerebral activity and yields information regarding polymorphism. It is thus possible to monitor variations in cerebral activity over a prolonged period during anaesthesia as well as during the revival phase with the Monitor of Cerebral Function, the electroencephalogram being reserved as an aid to precise diagnosis and for localization and close scruting of the anomalies.

Brain↗
PubMed1979

[Cerebral Function Monitor (CFM) and electroencephalography (EEG). Experimental study].

This work is an attempt to connect the electro-encephalogram (EEG) and monitor of cerebral function (MCF) recordings during the experimental stimulation of the rabbit brain whether this is in the from of direct central stimulation, by stereotaxic location, or in the form of indirect stimulation via a peripheral nerve. These stimulations, performed under alfadione anaesthesia or under the neuroleptanalgesic sedative effect of chlorprothixine, are compared for every animal with the results of the control stimulations. The cardiovascular responses are recorded simultaneously. It has been found that, in simple narcosis induced by alfadione, there is much variation in the EEG recording and even more so in the MCF recording according to the quantity used and the block of responses to stimuli does not appear until there is deep anaesthesia. However, when chlorprothixine is used, the MCF trace is found to be very closely related to the trace of mild anaesthesia with accompanying block to all of the nociceptive stimulations. It would seem, therefore, if we accept the concept of levels of cerebral activity, that the use of the MCF could well open the way to a better understanding of the pure narcotic phenomena and of the neurovegetative response block to aggression.

Alfaxalone Alfadolone Mixture↗
PubMed1979

[Use of the Cerebral Function Monitor in the study of physiological sleep].

After a brief description of the different phases of physiological sleep, the reasons for employing a new appatus, the Monitor of Cerebral Function, are discussed. This instrument, the first designed for continual monitoring of cerebral activity may be employed in neurophysiology. The results obtained are presented, i.e. the demonstration of a perfect correlation between the Monitor of Cerebral Function recording and the polygraphic methods. The paradoxal and rapid phases of sleep are easily distinguished. The study of paradoxal sleep, both in physiology and in pharmacology, could profit greatly from the use of the MCF due to the great advantage of its ease of operation.

Adult↗
PubMed1977

A study of eye movement for assessing recovery from anaesthesia.

A test for assessing recovery from general anaesthesia is proposed, using electro-oculographic (e.o.g.) measurements. The eyes, when exploring a flat area, progress by "jerking" movements. After general anaesthesia, incomplete recovery is associated with smooth sinusoidal movements. In a series of 16 patients, different e.o.g. patterns were compared with clinical signs of awakening and related to the anaesthetic drugs used. In a further group of 19 patients, assessment of recovery using e.o.g. techniques was made 2 h following the end of operation. In both groups, this simple test appeared to be very reliable. In addition, the test provides a record which can be filed. This may be of value in day-case anaesthesia, where the safety of the patient and medicolegal considerations would be aided by an objective measurement of recovery.

Anesthesia, General↗
PubMed1976

[Electromyography and AH/8165 in man].

This article concerns the electromyographical study of a synthetic curare derived from Azobis Arylimidazo (1-2a) Pyridinium (AH/8165) with a simultaneous recording of the spontaneous diaphragmatic activity and "testing" of the neuro-muscular transmission at the level of a peripheral muscle. This study shows that AH/8165 is a powerful non-depolirizing curarimimetic drug that quickly induces a neuro-muscular block at the level of the diaphragm and the peripheric muscles that can be reversed by anticholinesterasic drugs. Its reaction time is short (about 1 mn). There are importante individual variations in the duration of the neuromuscular blockage. Towards the end of the experience, tetanizing stimulations reveal a muscular fatigability in all the cases. No ill side-effects could be observed upon the cardiovascular system or any side-effects ascribable to a histaminergic mechanism.

Curare↗
PubMed1976

[Neuroplegia: results of an interdisciplinary approach to its physiopathology].

Neuroplegia was born from a physiopathological study of states of shock and research on inhibition of the autonomic reaction to aggression. Over the last 25 years, the experimental facts have become accumulated in favour of the first theory of H. Laborit, i.e. that this so-called defence reaction defended our lives only through conservation of motor activity in the environment. When this motor activity is inefficacious or useless, the neuroendocrine reaction may lead, during the acute phase, to states of shock and to chronic psychosomatic pathology. On this general theme, inhibition of this reaction by neuroplegic drugs, among which the phenothiazine derivatives have played a very important role, has led in numerous surgical and medical disciplines, to basic research and therapeutic consequences. Thus, in anesthetics, it was at the origin of potentialised anesthesia, then neuroleptanalgesia. In general intensive care, it is used in various ways in the study and treatment of states of shock. In psychiatry, it has initiated neuro-psychopharmacology and the neuro-physiological and biochemical study of the nervous system in its response to the psycho-social environment. It has found its place in anesthesia and in obstetric pathology. But above all, has led pharmacologists to the study of metabolic and biochemical activities. The result of an interdisciplinary approach, neuroplegia has on the contrary, often been the origin of an interdisciplinary development of our physiological and physiopathological knowledge. Today this development seems to better understand its mode of action at various levels of organisation of living systems. One may thus say that neuroplegia, apart from its therapeutic interest, has been a good working instrument and led to better understanding of numerous biological disciplines.

Adrenal Glands↗
PubMed1976

[Neuroplegia in cranial and cranio-thoracic injuries].

During severe head injuries, the reaction to the cerebral lesion is intense and characterised by a disturbance which is automatic, vasomotor and endocrine. Associated with general ventilatory and nutritional resuscitation, neuroplegia occupies in this pathology, aplace of choice. Cranio-thoracic traumas raise more complex problems owing to different ventilatory requirements, depending on whether the lesion is of the brain or thorax. One must therefore, find a compromise between the depression which necessarily occurs during a too intense autonomic reaction, and the ventilatory requirements created by the thoracic injury. In all cases, the micro-circulatory improvement produced by neuroplegic drugs is probably favourable. The authors report their experience of eighty severe cranio-thoracic traumas, over a period of thirty months, submitted to treatment including neuroplegics.

Adrenergic alpha-Antagonists↗
PubMed1976

[Corticoids and shock].

After recalling the major role of catecholamines in the genesis of irreversible shock, the anti-shock action of glucocorticosteroids, owing to properties which are "alpha-blocking" , is discussed in this work. The works of LILLEHEI on the effectiveness of corticosteroids in different types of shock are summarized and discussed, as well as numerous works which have followed and a synopsis of which, done in 1967 in the "Annales de l'Anesthésiologie Francaise", is presented. Since then, following new experimental facts, whereas numerous contradictions have appeared in the clinical and experimental realms, the possible mechanisms of action of corticosteroids in shock are looked at, by emphasizing the relationships between corticosteroids and SHWARTZMAN's phenomenon, in particular. A hypothesis on a probable central action of glucocorticosteroids is proposed following experimental works carried out by H. LABORIT et Coll. (1975). Finally, the author presents a personal experiment in hemorrhagic shock in the rabbit where the adjunction of corticosteroids had no effect on the different parameters such as the decrease in PaCO2, hyperlactacidemia and the liberation of beta-glycuronidase in the blood, mortality being practically the same in the controls and in the animals submitted to corticosteroid therapy.

Adrenal Cortex Hormones↗
PubMedDate not supplied

[Monitoring the integrity of saccadic eye movements as a test of post-anaesthetic recovery (author's transl)].

After reviewing various tests of consciousness which can be used during the post-anaesthetic period, the authors chose to analyse the involvement of the visual receptor during different stages between sleep and complete recovery of consciousness, by an electro-oculographic (EOG) method, providing recordings of the displacement of the optical axis. In states of full consciousness the eye explores a static flat surface in saccades separated by pauses. During sleep caused by anaesthesia or by other types of drugs, the integrity of the eye positioning movements by saccades is impaired, and the EOG shows a sinusoidal recording (smooth movements). In one group of patients, regaining of consciousness was monitored throughout and the EOG reording reflected the clinical state of the patient. In a second group, the state of consciousness was monitored 2 hours after the last injection of the anaesthetic drug, so that correlations could be considered with the type of anaesthesia used. Th conclusion concerns the practical interest of the method (short term hospitalisation after general anaesthetic, medico-legal use due to the existence of a recording) and its basic use in the experimental study of new drugs in man.

Anesthesia, General↗
PubMedDate not supplied

[Iskedyl and general anesthesia. Measurement of the systolic ejection volume and peripheral resistance using the arterial pressure curves].

ISKEDYL (PF 50), which is sold as a vasoregulator of cerebral irrigation, consists of a mixture of dihydroergocristine and raubasine. This work aims at determining possible interactions between this product and certain drugs used in anesthesia from the cardiovascular point of view. ISKEDYL does not seem to be a contraindication to anesthesia of the "neuroleptic" type, when injected in pre-, per- or post-operative period. A slight temporary and spontaneously reversible fall in arterial blood pressure, affecting both maximum and minimum pressure, together with a decrease in stroke volume and peripheral resistances, estimated by the study of the arterial blood pressure curve, seem to indicate that this product has peripheral vaso-dilatory properties.

Anesthesia, General↗