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M Jouvet

Publications and source records attributed to M Jouvet.

At least 199 records · Page 11Linked to original sources
PubMed1985

[Value of the sleep diary in the study of vigilance dis].

This study presents an easy and practical subjective method for evaluating vigilance disorders: the sleep diary. We used it in hypersomnia and deficits of waking. Sleep diaries were filled in by 10 control and 22 hypersomniac subjects. Twenty-four hour polyhypnographic recording allowed the classification of hypersomnia as 13 narcolepsies, 9 hypersomnias with a prevalence of PS, 2 'harmonious' hypersomnias and 1 waking deficit. The sleep diary data (amount of nocturnal sleep and diurnal sleep onset and vigilance decrease) were compared with polygraphic results. According to the diary data, 3 groups of hypersomnia appeared with regard to the time at which sleep onset occurred. The first group presented an increase of sleep onsets at 2 p.m. In the second group, almost exclusively composed of narcoleptic subjects, sleep onsets occurred every 2 h and in the third group they were distributed throughout the day. These results suggest different physiological mechanisms for these 3 groups of hypersomnia. Finally, the sleep diary seems to be an easy and cheap method of evaluating vigilance disorders in hypersomniac subjects during their everyday life.

Adult↗
PubMed1985

Factors influencing the properties of voltammetric carbon fibre electrodes: the importance of the pH of the medium used for the electrical treatment and of the resin coating of the fibres.

Electrical treatment of resin-coated voltammetric carbon fibre electrodes with triangular voltage at low (1.1) pH resulted in electrodes almost insensitive to ascorbic acid (AA) and dihydroxyphenylacetic acid (DOPAC) while their response to 5-hydroxyindoleacetic acid (5-HIAA) was practically the same as after treatment in the usually employed pH 7.4 medium. Electrodes treated at high pH (12.0), on the other hand, were more sensitive to AA and DOPAC than those treated at pH 7.4 and less sensitive to 5-HIAA. Exposing resin-coated electrodes to the treatment media without electrical treatment was not sufficient to obtain the same results as with the application of the current. Electrodes without resin coating were sensitive to AA without electrical treatment while coated electrodes were not. Electrical treatment increased the sensitivity of non-coated electrodes and rendered coated electrodes even more sensitive than non-coated ones. Treatment of coated electrodes for a maximum sensitivity to 5-HIAA was found to require less time than to obtain maximum sensitivity to the other compounds. Present results suggest that it is possible to prepare selective voltammetric electrodes by choosing the right parameters for their electrical pretreatment.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1985

Diurnal administration of human growth hormone-releasing factor does not modify sleep and sleep-related growth hormone secretion in normal young men.

hGRF (iv 50 micrograms) was administered to 6 normal young adult males at 09.00 and 20.00 h on different days. Nocturnal GH secretion was monitored during polygraphic sleep recordings on both control nights and nights following hGRF administration. Sleep-related GH secretion and sleep parameters were not affected by diurnal hGRF administration.

Adult↗
PubMed1985

[Neonatal development of ACTH-immunoreactive neurons in the rat].

Using immunohistochemical techniques, the distribution of ACTH 25-39 immunoreactive perikarya and fibers was studied in the newborn rat. Perikarya and fibers were demonstrated on day 1 after birth in the diencephalon, mesencephalon, pons and medulla. However, the amount of material increased rapidly from the first to third day of postnatal development.

Adrenocorticotropic Hormone↗
PubMed1985

[Insomnia caused by administration of para-chlorophenylalanine: reversibility by peripheral or central injection of 5-hydroxytryptophan and serotonin].

Parachlorophenylalanine (PCPA) produces a total insomnia with a permanent discharge of pontogeniculooccipital (PGO) activity. We studied the reversibility of this insomnia in physiological slow-wave sleep (SWS) and paradoxical sleep (PS) after 5-hydroxytryptophan (5HTP) and serotonin (5HT) administration. Whereas D-5HTP (5 mg/kg) had no effect, parenteral injection of L-5HTP (2.5 mg/kg) or DL-5HTP (5 mg/kg) immediately suppressed PGO activity, then gave rise to the return of SWS and PS with delays of 26 and 60 min, respectively. Intraventricular or intracisternal administration of 5HTP (250 to 1500 micrograms) or 5HT produced physiological sleep with variable delays. If chloramphenicol (which selectively suppresses PS in normal cat) is administered in a PCPA-pretreated cat, 5HTP still suppressed PGO activity and gave rise to a lower amount of SWS but did not restore PS. The results suggest that 5HTP is rapidly decarboxylated into 5HT in restoring the PGO gating effect. Thus, 5HT would seem to act as a classic neurotransmitter. The long latency for PS (and its suppression by chloramphenicol) suggests that 5HT would appear to be a neurohormone controlling another sleep-inducing factor.

5-Hydroxytryptophan↗
PubMed1984

Monoamine oxidase-containing neurons in the cat hypothalamus: distribution and ascending projection to the cerebral cortex.

Using a recently developed monoamine oxidase (MAO) histochemical technique, we show the existence of MAO-containing neurons in the cat hypothalamus. In conjunction with retrograde tracer technique with horseradish peroxidase, we further demonstrate that virtually all posterior hypothalamic neurons projecting directly to the occipital cortex contain MAO, an amine catabolizing enzyme.

Animals↗
PubMed1984

Effect of lesion of subcommissural organ on sleep in cat.

We examined the possibility that subcommissural organ is implicated in the mechanisms of sleep-waking cycle. Electrolytic lesions of this structure were performed in two cats without disturbing the organization of sleep nor modifying the daily quantities of paradoxical sleep and slow-wave sleep. These results indicate that subcommissural organ does not play a major role in sleep mechanisms.

Animals↗
PubMed1984

Differential pulse voltammetric determination of 5-hydroxyindoles in four raphe nuclei of chronic freely moving rats simultaneously recorded by polygraphic technique: physiological changes with vigilance states.

Nuclei raphe dorsalis ( RDN ), centralis (RCN), pontis (RPN) and magnus ( RMN ) were separately studied using differential pulse voltammetry ( DPV ) in chronic freely moving rats during the recording of their sleep-waking cycle by polygraphic technique. In each of these nuclei the height of the electrochemical signal appearing at +300 mV (peak 3) was maximum during waking (W), lower during slow-wave sleep (SWS) and minimum during paradoxical sleep (PS). Some pharmacological treatments indicated that in each of these nuclei the peak 3 represents the oxidation of the 5-hydroxyindoles. DPV measurements performed during specific behavioral states (eating, grooming, washing, drinking) called active waking (AW) or manipulations (handling, tail-pinch) demonstrated that this technique enables detection of changes occurring in animals under physiological conditions.

Animals↗
PubMed1984

Effect of S-adenosyl-L-homocysteine upon sleep in p-chlorophenylalanine pretreated rats.

S-Adenosyl-L-homocysteine (7 mg/kg), administered to PCPA-pretreated rats, was able to restore normal SWS and PS quantities, as well as circadian rhythms. This effect was at its maximum when SAH was injected 48 h after PCPA (400 mg/kg). These results are discussed in terms of post-synaptic synergetic control by SAH of serotonergic and noradrenergic nerve terminals via the periventricular system and caudal medulla in relation to environmental input.

Animals↗
PubMed1984

Bulbo-thalamic neurons related to thalamocortical activation processes during paradoxical sleep.

Neurons histologically localized in the gigantocellular (Gc) and magnocellular (Mc) fields of the bulbar reticular formation were tested for antidromic invasion by stimulating the ventromedial (VM) and intralaminar (centralis lateralis, CL, and centrum medianum, CM) thalamic nuclei, midbrain reticular formation (MRF), and reticulospinal tract. An overwhelming majority (94%) of antidromically identified cells projected either to rostral structures (MRF, medial and intralaminar thalamic nuclei) or to the spinal cord, while only 6% had bifurcating axons. Rostrally projecting bulbar reticular neurons were investigated during various wake-sleep behavioral states. (a) Phasic neurons were related to PGO waves, eye and head movements, and were localized in both Gc and Mc fields. (b) The majority of tonic neurons projected to MRF and VM and they were localized within Mc in a proportion of 85%. In order to test their possible role in activation of thalamocortical processes (as betrayed by EEG desynchronization), the activity of tonically discharging cells was separately evaluated in periods with and without phasic motor events. Half of the tonically discharging neurons had a high selectivity of discharge during paradoxical sleep without REM bursts (PS-); the ratio of their mean discharge rate during PS- to that in quiet wakefulness ( QW ) or slow-wave sleep (SWS) was 8 and 6, respectively. The other half of the tonic neurons equally increased firing rates from SWS to either QW or PS. The firing rate of rostrally projecting bulbar reticular neurons with tonic discharge patterns was analyzed during transitions from SWS to PS. An increase in discharge rate was found about 30 to 60 s prior to the first sign of EEG desynchronization in PS, during fully synchronized sleep with PGO waves (S-PGO). Statistical testing showed that the increased firing rate was not associated to PGO waves, but was temporally related to the appearance of EEG desynchronization at PS onset. We conclude, on the basis of these and other recent data, that tonically discharging bulbar reticular neurons with identified projections to the midbrain and thalamic nuclei act synergically with rostrally projecting MRF neurons as sources of thalamocortical activation.

Animals↗
PubMed1984

Has the raphe dorsalis nucleus an asymmetric function?

Differential pulse voltammetry (DPV) was used to measure 5-hydroxyindoles in the striata of anaesthetized rats. The amplitude of the voltammetry peaks in both striata decreased when 5-hydroxytryptophan (5-HTP) or 5-hydroxytryptamine (5-HT) was injected into the left side of the raphe dorsalis nucleus (RDN), but increased when either substance was injected into the right side. These findings indicate that the 5-hydroxyindole based communication between the striata and the RDN has a lateral asymmetry. The data are discussed with reference to histological observations suggesting a higher density of 5-hydroxyindole containing cell bodies in the lateral region than in the midline of this "unpaired" nucleus.

5-Hydroxytryptophan↗
PubMed1984

5-HT immunoreactive hypothalamic neurons in rat and cat after 5-HTP administration.

Using immunohistochemistry for serotonin (5-HT) after administration of 5-hydroxytryptophan (5-HTP), we have demonstrated the existence of a particular group of 5-HT accumulating neurons in the posterior hypothalamus of the rat and cat. This cluster of neurons, which we termed "5-HT immunoreactive (IR) posterior hypothalamic magnocellular neurons," was characterized by: (1) diffuse 5-HT-IR staining; (2) rather large-sized cell bodies; (3) a marked activity of monoamine oxydase (MAO); (4) capacity of uptake and decarboxylation of 5-HTP; and (5) the absence of capacity of uptake and hydroxylation of tryptophan. These 5-HT-IR magnocellular neurons extended from the suprachiasmatic nucleus area to the caudal end of the hypothalamus. In the rat, the majority of these neurons was found in the tuberal and caudal magnocellular nuclei, whereas in the cat, it was found more widespread in the ventrolateral part of the posterior hypothalamus including the tuberomamillary nucleus. The characteristics of the 5-HT-IR magnocellular neurons which project directly both to the cerebral cortex and the pontine tegmentum are discussed in comparison with those of "APUD" cell series or "paraneurons," as well as with those of other 5-HT-IR neurons demonstrated in the hypothalamus after administration of 5-HTP or tryptophan.

5-Hydroxytryptophan↗
PubMed1984

Possible role of serotonin in the secretory activity of the subcommissural organ of the cat.

The possible role of serotonin (5-hydroxytryptamine, 5-HT) in the secretory activity of the subcommissural organ (SCO) was investigated in the cat by using 5-HT immunohistochemistry and Gomori's secretory staining technique. Administration of para-chlorophenylalanine, a potent inhibitor of 5-HT synthesis, was found to produce a marked decrease in both 5-HT-immunoreactive materials and secretory granules in the SCO. In contrast, administration of 5-hydroxytryptophan, an immediate precursor of 5-HT, to animals pretreated with para-chlorophenylalanine resulted in an increase in the amount of both secretory granules and 5-HT immunoreactivities in this circumventricular organ. These results strongly suggest that the secretory activity of the SCO of cats is regulated by 5-HT.

Animals↗
PubMed1984

[Neuromediators and hypnogenic factors].

The concept of hypnogenic factor(s) which could increase during sleep deprivation was initiated by Piéron in 1913. However this idea was not accepted. It is difficult indeed to differentiate a true sleep inducing factor from the numerous exogeneous or endogeneous factors which may facilitate sleep onset, slow wave sleep (SWS) and/or paradoxical sleep (PS). At the present time there is no true sleep inducing factor for which it has been proven that its inactivation would led to long lasting selective insomnia. A review of the effect of central peptides upon the sleep waking cycle of rats does not permit to isolate any true "sleep" peptide. Only vaso-intestinal peptide (VIP) has some true hypnogenic effect since its injection is able to restore sleep in insomniac PCPA pretreated rats. The serotonergic system of the raphe was considered first as a true hypnogenic system since its inactivation by lesion or inhibition of 5HT biosynthesis with PCPA led to a total insomnia which could be reversed into physiological sleep by a secondary injection of 5HTP (the direct precursor of 5HT). This hypothesis has been rejected recently. Indeed, it has been shown that the activity of 5HT neurons was higher during waking than during sleep. Moreover the release of 5HT and 5HIAA (as measured with voltametric method) is also higher during waking. The following hypothesis may solve these contradictions: when 5HT neurons are active during waking, they initiate through neurohormonal mechanisms the biosynthesis of sleep factor(s) which are stored until they trigger sleep. Thus the amount of waking may be correlated with subsequent sleep. Recent experiments favor the hypothesis of the 5HT directed biosynthesis of PS factor which may trigger PS even in PCPA pretreated cats which are depleted of 5HT. On the one hand, PCPA injection during PS instrumental deprivation is followed by a subsequent PS rebound despite 5HT depletion. On the other hand, transfer of CSF from a normal sleep deprived donor cat induces PS in a PCPA pretreated insomniac recipient cat.

Animals↗
PubMed1984

[Specific neurons for wakefulness in the posterior hypothalamus in the cat].

Using a single unit recording technique in freely moving Cats, we have demonstrated the presence of two groups of neurons in the ventrolateral part of the caudal hypothalamus. One is characterized by a tonic discharge during waking and paradoxical sleep, the other is highly selective to the waking state. This group of neurons showed a slow tonic and regular discharge during wakefulness, a significant decrease in firing rate during stage I slow-wave sleep and a complete cessation of firing during stage II slow-wave sleep and subsequent paradoxical sleep.

Animals↗