References of "Ansseau, Marc"
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See detailRelationships between DRD2 and DAT polymorphisms and personality traits in healthy subjects
Pinto, Emmanuel ULg; Reggers, Jean ULg; Adam, Martine ULg et al

in European Neuropsychopharmacology (2003, September), 13(Suppl. 4), 427-428

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See detailToxicomanes: sevrage ultrarapide aux opiacés sous anesthésie générale au CHU de Liège
Pinto, Emmanuel ULg; Reggers, Jean ULg; Fuchs, S. et al

in Agenda Psychiatrie (L') (2003), 28

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See detailMismatch negativity is not correlated with neuroendocrine indicators of catecholaminergic activity in healthy subjects.
Hansenne, Michel ULg; Pinto, Emmanuel ULg; Scantamburlo, Gabrielle ULg et al

in Human Psychopharmacology (2003), 18(3), 201-5

The identification of the brain structures and neurotransmitters responsible for the generation and/or modulation of the mismatch negativity (MMN) may contribute to a clearer understanding of its ... [more ▼]

The identification of the brain structures and neurotransmitters responsible for the generation and/or modulation of the mismatch negativity (MMN) may contribute to a clearer understanding of its functional significance, and may have clinical implications. In this context, some findings suggest that the scalp-recorded MMN reflects activity from multiple neuronal ensembles within or in the immediate vicinity of the primary auditory cortex and with possible contribution from the frontal cortex. However, few data are available concerning the influence of neurotransmitter systems on the MMN. In this study, the relationship between both noradrenergic and dopaminergic systems and the MMN were investigated in 34 healthy volunteers. Noradrenergic and dopaminergic activities were assessed with the apomorphine and clonidine challenge tests. The results showed no significant relationship between either growth hormone (GH) responses to apomorphine or clonidine and the MMN amplitude or latency. Therefore, this study does not demonstrate the implication of dopaminergic and noradrenergic activities as assessed by GH response to apomorphine and clonidine for the generation and/or the modulation of the MMN. However, given the complexity of the central neurotransmitter systems, these results cannot be considered as definitive evidence against a relationship between dopaminergic and noradrenergic activity and the MMN. [less ▲]

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See detailHarm avoidance is related to mismatch negativity (MMN) amplitude in healthy subjects
Hansenne, Michel ULg; Pinto, Emmanuel ULg; Scantamburlo, Gabrielle ULg et al

in Personality & Individual Differences (2003), 34(6), 1039-1048

Event-related potential (ERP) studies evidenced that some personality dimensions induced different controlled cognitive attitudes towards the processing of information. However, few data are available on ... [more ▼]

Event-related potential (ERP) studies evidenced that some personality dimensions induced different controlled cognitive attitudes towards the processing of information. However, few data are available on the possible relationships between personality and automatic attention or early sensory processing. In the present study the relationships between the mismatch negativity (MMN) and personality described by the Cloninger model of personality were investigated. Subjects were 32 healthy volunteers. The MMN was recorded with frequent stimuli tones of 1470 Hz, 70 dB and 40 ms duration, and target (20%) tones of 1470 Hz, 70 dB, 80 ms duration. The subjects completed a French version of the 226-item self-questionnaire TCI within the day following psychophysiological recording. The results showed that the HA dimension was negatively correlated with the MMN amplitude. The association was more present among women than men. No significant relationship existed between the other dimensions of personality and either the MMN amplitude or latency. These findings suggest that the MMN is related to the behavioral inhibition system (BIS), a fact which is consistent with clinical studies conducted on schizophrenia and anxiety disorders. In conclusion, this study suggests that personality dimensions induce different automatic attitudes towards the processing of information. (C) 2002 Published by Elsevier Science Ltd. [less ▲]

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See detailEvent-related potentials to emotional and neutral stimuli in alcoholism.
Hansenne, Michel ULg; Olin, Cecile; Pinto, Emmanuel ULg et al

in Neuropsychobiology (2003), 48(2), 77-81

Several studies have demonstrated that the emotional value of stimuli affects P300 amplitude. In the present study, the influence of alcohol-related stimuli in alcoholic patients was investigated ... [more ▼]

Several studies have demonstrated that the emotional value of stimuli affects P300 amplitude. In the present study, the influence of alcohol-related stimuli in alcoholic patients was investigated. Subjects were 10 alcoholic inpatients (3 female) and 10 age- and sex-matched controls. Eight alcohol-related and 8 neutral words served as stimuli in a visual oddball paradigm. Acohol-related words were targets (48 stimuli, 33%) and neutral words were standard stimuli (96 stimuli, 66%). Results showed that P300 amplitude for targets did not differ significantly between the two groups. However, P300 latency for targets as well as reaction time were significantly shorter in male alcoholic patients. In contrast, P300 latency was increased in female alcoholic patients but reaction time did not differ. These results suggest that male alcoholics process information linked to alcohol cues more rapidly than neutral cues, probably because a specific semantic network is activated in these patients. The decreased reaction time confirms the impulsive behavior frequently found in male alcoholism, as it has been described in type II alcoholism. Besides, the results imply that information processing was delayed in female alcoholic patients. Therefore this study demonstrates a gender-dependent impact of alcohol-related stimuli on information processing. [less ▲]

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See detailLipides, dépression et suicide
Colin, A.; Reggers, Jean ULg; Castronovo, Vincenzo ULg et al

in Encéphale (L') (2003), 29(1, JAN-FEB), 49-58

Polyunsatured fatty acids are made out of a hydrocarbonated chain of variable length with several double bonds. The position of the first double bond (omega; omega) differentiates polyunsatured omega3 ... [more ▼]

Polyunsatured fatty acids are made out of a hydrocarbonated chain of variable length with several double bonds. The position of the first double bond (omega; omega) differentiates polyunsatured omega3 fatty acids (for example : alpha-linolenic acid or alpha-LNA) and polyunsatured omega6 fatty acids (for example : linoleic acid or LA). These two classes of fatty acids are said to be essential because they cannot be synthetised by the organism and have to be taken from alimentation. The omega3 are present in linseed oil, nuts, soya beans, wheat and cold water fish whereas omega6 are present in maize, sunflower and sesame oil. Fatty acids are part of phospholipids and, consequently, of all biological membranes. The membrane fluidity, of crucial importance for its functionning, depends on its lipidic components. Phospholipids composed of chains of polyunsatured fatty acids increase the membrane fluidity because, by bending some chains, double bonds prevent them from compacting themselves perfectly. Membrane fluidity is also determined by the phospholipids/free cholesterol ratio, as cholesterol increases membrane viscosity. A diet based on a high proportion of essential polyunsatured fatty acids (fluid) would allow a higher incorporation of cholesterol (rigid) in the membranes to balance their fluidity, which would contribute to lower blood cholesterol levels. Brain membranes have a very high content in essential polyunsatured fatty acids for which they depend on alimentation. Any dietary lack of essential polyunsatured fatty acids has consequences on cerebral development, modifying the activity of enzymes of the cerebral membranes and decreasing efficiency in learning tasks. Epidemiological data - The prevalence of depression seems to increase continuously since the beginning of the century. Though different factors most probably contribute to this evolution, it has been suggested that it could be related to an evolution of alimentary patterns in the Western world, in which polyunsatured omega fatty acids contained in fish, game and vegetables have been largely replaced by polyunsatured omega6 fatty acids of cereal oils. Some epidemiological data support the hypothesis of a relation between lower depression and/or suicide rates and a higher consumption of fish. These data do not however prove a relation of causality. Cholesterol and depression - Several cohort studies (on nondepressed subjects) have assessed the relationship between plasma cholesterol and depressive symptoms with contradictory results. Though some results found a significant relationship between a decrease of total cholesterol and high scores of depression, some other did not. Studies among patients suffering from major depression signalled more constantly an association between low cholesterol and major depression. Besides, some trials showed that clinical recovery maybe associated with a significant increase of total cholesterol. Cholesterol and suicidal behaviour - The hypothesis that a low cholesterol level may represent a suicidal risk factor was discovered accidentally following a series of epidemiological studies which revealed an increase of the suicidal risk among subjects with a low cholesterol level. Though some contradictory studies do exist, this relationship has been confirmed by several subsequent cohort studies. These findings have challenged the vast public health programs aimed at promoting the decrease of cholesterol, and even suggested to suspend the administration of lipid lowering drugs. Recent clinical studies on populations treated whith lipid lowering drugs showed nevertheless a lack of significant increase of mortality, either by suicide or accident. In addition, several controlled studies among psychiatric patients revealed a decrease of the concentrations of plasma cholesterol among patients who had attempted suicide in comparison with other patients. Polyunsaturated fatty acids and depression - In major depression, all studies revealed a significant decrease of the polyunsaturated omega3 fatty acids and/or an increase of the omega6/omega3 ratio in plasma and/or in the membranes of the red cells. In addition, two studies found a higher severity of depression when the level of polyunsaturated omega fatty acids or the ratio omega3/omega6 was low. Parallel to these modifications, other biochemical perturbations have been reported in major depression, particularly an activation of the inflammatory response system, resulting in an increase of the pro-inflammatory cytokines (interleukins: IL-1beta, IL-6 and interferon gamma) and eicosanoids (among others, prostaglandin E2) in the blood and the CSF of depressed patients. These substances cause a peroxidation and, consequently a catabolism of membrane phospholipids, among others those containing polyunsaturated fatty acids. The cytokines and eicosanoids derive from polyunsaturated fatty acids and have opposite physiological functions according to their omega or omega6 precursor. Arachidonic acid (omega6) is, among others, precursor of pro-inflammatoty prostaglandin E2 (PGE2), whereas polyunsaturated W fatty acids inhibit the formation of PGE2. It has been shown that a dietary increase of polyunsaturated W fatty acids reduced strongly the production of IL-1beta, IL-2, IL-6 and TNF-alpha (tumor necrosis factor-alpha). In contrast, diets with a higher supply of linoleic acid (omega6) increased significantly the production of pro-inflammatory cytokines, like TNF-alpha. Therefore, polyunsaturated omega3 fatty acids could be associated at different levels in the pathophysiology of major depression, on the one hand through their role in the membrane fluidity which influences diverse steps of neurotransmission and, on the other hand, through their function as precursor of pro-inflammatory cytokines and eicosanoids disturbing neurotransmission. In addition, antidepressants could exhibit an immunoregulating effect by reducing the release of pro-inflammatory cytokines, by increasing the release of endogenous antagonists of pro-inflammatory cytokines like IL-10 and, finally, by acting like inhibitors of cyclo-oxygenase. Therapeutic use of fatty acids - Data available concerning the administration of supplements of DHA (docosahexanoic acid) or other polyunsaturated fatty acids omega3 are limited. In a double blind placebo-controlled study on 30 patients with bipolar disorder, the addition of polyunsaturated omega3 fatty acids was associated with a longer period of remission. Moreover, nearly all the other prognosis measures were better in the omega3 group. Very recently, a controlled trial showed the benefits of adding an omega3 fatty acid, eicosopentanoic acid, among depressed patients. After 4 weeks, six of the 10 patients receiving the fatty acid were considered as responders in comparison with only one of the ten patients receiving placebo. Conclusions Some epidemiological, experimental and clinical data favour the hypothesis that polyunsaturated fatty acids could play a role in the pathogenesis and/or the treatment of depression. More studies however are needed in order to better precise the actual implication of those biochemical factors among the various aspects of depressive illness. [less ▲]

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See detailVenlafaxine: the relationship between dose, plasma concentration and clinical response in depressive patients
Charlier, Corinne ULg; Pinto, Emmanuel ULg; Ansseau, Marc ULg et al

in Journal of Psychopharmacology (2002), 16(4), 369-372

The relationship between plasma drug level of venlafaxine and daily intake was studied in 89 major depressive inpatients. In addition, changes over time in severity were assessed weekly in a subgroup of ... [more ▼]

The relationship between plasma drug level of venlafaxine and daily intake was studied in 89 major depressive inpatients. In addition, changes over time in severity were assessed weekly in a subgroup of 22 depressed patients using the Montgomery and Asberg Depression Rating Scale (MADRS) and the Clinical Global Impression improvement scale. The results indicate a moderate correlation between daily doses and plasma concentrations, together with a higher relationship between improvement on the MADRS scale and concentration. Moreover, plasma concentrations (for venlafaxine and its predominant metabolite, O-desmethylvenlafaxine) up to 400 microg/l can be considered as effective, as already suggested in a previous study. No case of venlafaxine discontinuation occurred during the longitudinal study, and the incidence of adverse event, as estimated by the Target Emergent Symptoms and Side-effects scale, was low, suggesting that the drug is well tolerated for such plasma concentrations. [less ▲]

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See detailTroubles anxieux et pathologies organiques: un diagnostic differentiel difficile
Scantamburlo, Gabrielle ULg; Fuchs, Sonia; Lancellotti, Patrizio ULg et al

in Revue Médicale de Liège (2002), 57(5), 303-306

The diagnostic criteria for panic disorder include symptoms commonly experienced by patients with organic diseases. We report a case of coronary artery spasm in a patient with chest pain, exhibiting ... [more ▼]

The diagnostic criteria for panic disorder include symptoms commonly experienced by patients with organic diseases. We report a case of coronary artery spasm in a patient with chest pain, exhibiting atypical characteristics, and accompanied by symptoms of nervousness. The approach and the management of anxiety disorders are discussed. [less ▲]

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See detailFurther evidence on the relationship between dopamine and novelty seeking: a neuroendocrine study
Hansenne, Michel ULg; Pinto, Emmanuel ULg; Pitchot, William ULg et al

in Personality & Individual Differences (2002), 33(6), 967-977

In the biosocial model of Cloninger, three major personality dimensions, novelty seeking (NS), harm avoidance (HA), and reward dependence (RD) are dependent on central monoaminergic systems, respectively ... [more ▼]

In the biosocial model of Cloninger, three major personality dimensions, novelty seeking (NS), harm avoidance (HA), and reward dependence (RD) are dependent on central monoaminergic systems, respectively dopaminergic, serotonergic, and noradrenergic. This study investigated the relationships between these major personality dimensions and growth hormone (GH) responses to both apomorphine and clonidine challenge tests in healthy subjects. GH responses to apomorphine were significantly correlated with NS when peak relative values were considered (r=0.47, P=0.03). HA and RD did not show any relationships with the endocrine responses. In contrast, no significant relationship existed between GH responses to clonidine and any of the three temperament dimensions. These results gave another support of the hypothesized link between NS and dopaminergic central neurotransmission. In contrast, the results did not confirm the association between RD and noradrenergic central neurotransmission, probably because RD is poorly validated. This partial confirmation might suggest that the link between personality traits and neurotransmission systems is probably indirect. (C) 2002 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailTroubles anxieux et pathologies organiques: un diagnostic differentiel difficile.
Scantamburlo, Gabrielle ULg; Fuchs, S.; LANCELLOTTI, Patrizio ULg et al

in Revue Médicale de Liège (2002), 57(5), 303-6

The diagnostic criteria for panic disorder include symptoms commonly experienced by patients with organic diseases. We report a case of coronary artery spasm in a patient with chest pain, exhibiting ... [more ▼]

The diagnostic criteria for panic disorder include symptoms commonly experienced by patients with organic diseases. We report a case of coronary artery spasm in a patient with chest pain, exhibiting atypical characteristics, and accompanied by symptoms of nervousness. The approach and the management of anxiety disorders are discussed. [less ▲]

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See detail5-HT1A dysfunction in borderline personality disorder.
Hansenne, Michel ULg; Pitchot, William ULg; Pinto, Emmanuel ULg et al

in Psychological Medicine (2002), 32(5), 935-41

BACKGROUND: A number of challenge studies have reported abnormalities of serotonergic function in borderline personality disorder (BPD). There are, however, problems with the pharmacological probes used ... [more ▼]

BACKGROUND: A number of challenge studies have reported abnormalities of serotonergic function in borderline personality disorder (BPD). There are, however, problems with the pharmacological probes used in these studies since fenfluramine and m-CPP are not only serotonergic agents but also induce release of catecholamines, particularly dopamine. Therefore, we tested whether subjects with BPD showed a blunted prolactin (PRL) response to flesinoxan, a highly potent and selective 5-HT1A agonist. METHODS: Flesinoxan challenge test was carried out in 20 BPD in-patients and 20 healthy controls matched for gender but not for age. Since 16 BPD in-patients exhibited major depressive co-morbidity, a group of 20 depressed in-patients matched for gender but not for age was also included. RESULTS: BPD in-patients exhibited blunted PRL responses as compared to controls, whereas depressed in-patients did not differ from controls. Moreover, PRL responses were lower among BPD in-patients than among depressed in-patients. Among the BPD in-patients, PRL responses to flesinoxan were lower in patients with past history of suicide attempts (N = 8) than in those with a negative history. CONCLUSIONS: The results show major involvement of serotonergic function in BPD and are consistent with previous studies linking lower serotonergic activity with impulsivity. More particularly, our data suggest that BPD is characterized by lower 5-HT1A receptor sensitivity. Moreover, the data support the involvement of 5-HT1A activity in suicidal behaviour. However, this conclusion is limited because other hormonal responses such as ACTH and cortisol were not assessed, and because BPD was assessed by a self-report questionnaire and not a structured clinical interview. [less ▲]

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See detailSerotonin, personality and borderline personality disorder
Hansenne, Michel ULg; Pitchot, William ULg; Ansseau, Marc ULg

in Acta Neuropsychiatrica (2002), 14(2), 66-70

Serotonin is one of the neurotransmitters implicated in normal personality Many psychobiological models of personality include,some dimensions related to serotonin. For instance, the harm avoidance ... [more ▼]

Serotonin is one of the neurotransmitters implicated in normal personality Many psychobiological models of personality include,some dimensions related to serotonin. For instance, the harm avoidance dimension of the blosocial model developed by Cloninger is related to serotonergic activity Higher scores on the harm avoidance dimension should theoretically reflect increased serotonergic activity However, correlation studies related serotonin activity to harm avoidance dimension have not yielded consistent findings. These controversial results are probably related to the complexity of the neurotransmitter systems, and the different assessment techniques used in these studies. Finally, recent genetic studies have examined the association between personality dimensions and serotonergic receptor polymorphisms with mixed results. Serotonin is not only related to some dimensions of normal personality Several psychopathological disorders are associated with serotonergic dysfunction. More particularly, borderline personality disorder (BPD) can be defined by many of the symptoms associated with serotonergic dysregulation, including affective lability, suicidal behaviours, impulsivity and loss of impulse control. Indeed, several reports have demonstrated the efficacy of selective serotonin re-uptake drugs in treating the depressive and impulsive symptoms of patients with BPD. Moreover, some challenge studies have reported a lower serotonergic activity in BPD. Because these challenges are not specific, we have assessed the serotonergic activity in BPD with the flesinoxan challenge. Preliminary results showed that the prolactine responses to flesinoxan were significantly lower in BPD patients compared to those observed in controls. [less ▲]

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See detailPsychological distress of surgical patients after orthotopic heart transplantation
Triffaux, Jean-Marc ULg; Wauthy, Jacques ULg; Albert, Adelin ULg et al

in Transplant International (2001), 14(6), 391-395

Orthotopic heart transplantation (OHT) is a major surgical intervention inducing distress and anxiety. Psychological problems after OHT have been described in many studies. Little is known, however, about ... [more ▼]

Orthotopic heart transplantation (OHT) is a major surgical intervention inducing distress and anxiety. Psychological problems after OHT have been described in many studies. Little is known, however, about the relationship between the psychological state of the patient and time after surgery. The present study involved 41 consecutive OHT patients that underwent transplantation from January 1991 to December 1992, with a retrospective review of pretransplant psychiatric evaluations to define a Diagnostic and Statistical Manual of Mental Disorders, 3rd edn., revised (DSM III-R) Axis I diagnosis. Patients completed the Beck Depression Inventory (BDI-13), Spielberger's State Trait-Anxiety Inventory (STAI-Y), and the General Health Questionnaire (GHQ-28) between 1 and 41 months after transplantation. For comparison, 29 presumably healthy volunteers were given the same questionnaires. The study confirms the occurrence of abnormal psychological scores in the OHT group as compared to the reference population. Psychological scores, however, do not appear to be related to the time they were recorded after surgery. [less ▲]

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See detailPsychological Evolution and Assessment in Patients Undergoing Orthotopic Heart Transplantation
Triffaux, Jean-Marc ULg; Wauthy, Jacques ULg; Bertrand, Jean-Marie ULg et al

in European Psychiatry (2001), 16(3), 180-5

BACKGROUND: Orthotopic heart transplantation (OHT) is a major surgical intervention inducing distress and anxiety. Psychiatric evaluation of organ transplant candidates is now routinely proposed. This ... [more ▼]

BACKGROUND: Orthotopic heart transplantation (OHT) is a major surgical intervention inducing distress and anxiety. Psychiatric evaluation of organ transplant candidates is now routinely proposed. This study purposed to assess the psychological evolution in patients having received psychological and/or psychiatric assistance before and during 1-6 postoperative months. METHODS: Twenty-two consecutive transplant candidates were psychically evaluated as part of the preoperative protocol. In the waiting period, 1 and 6 months after OHT, they were asked to fill out the following questionnaires: the General Health Questionnaire, the Spielberger's State-Trait Anxiety Inventory, the Beck Depression Inventory, the Perceived Social Support Scale, the Toronto Alexithymia Scale and the Personal Reaction Inventory. RESULTS: A DSM-IV Axis I diagnosis was found in nine patients (41%); four patients (18%) presented with an Axis II diagnosis. One month after OHT, scores of depression, anxiety and general health significantly improved, while scores of social support, alexithymia and social desirability did not differ. In the sixth postoperative month, all psychological scores remained stable. CONCLUSIONS: A high prevalence of preoperative psychopathology was reported in 22 candidates who received OHT. Surgical intervention obviously improved the quality of life after cardiac transplantation. If the impact of psychological and/or psychiatric aid remains difficult to appraise, these results emphasize the positive impact of surgery on psychological status and the appropriateness of the psychosomatician's social support intervention on patients facing the transplant process. [less ▲]

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See detailIncidence des perturbations psychoendocriniennes au centre interdisciplinaire de l’andropause (CIA) du CHU de Liège : bilan des 7 premiers mois d’activité
Allouch, A; Bruwier, M; Comte-Tassin, M et al

in Annales d'Endocrinologie (2001), 62(4), 178

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See detailReply to Letter to the Editor
PITCHOT, William ULg; ANSSEAU, Marc ULg

in Psychoneuroendocrinology (2001)

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See detailLe médicament parmi les thérapies relationnelles : Enquête et réflexions.
David, Claire; WAUTHY, Jacques ULg; Vaulet, Véronique et al

in Revue des Hôpitaux de Jour Psychiatriques et des Thérapies Institutionnelles (2001)

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See detailAdding olanzapine to venlafaxine in treatment-refractory non-psychotic chronic depression
PITCHOT, William ULg; ANSSEAU, Marc ULg

in American Journal of Psychiatry (The) (2001)

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See detailVenlafaxine induced hair loss
PITCHOT, William ULg; ANSSEAU, Marc ULg

in American Journal of Psychiatry (The) (2001)

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See detailImplication de la neurohypophyse dans le stress psychique
Scantamburlo, Gabrielle ULg; Ansseau, Marc ULg; Legros, Jean-Jacques ULg

in Encéphale (L') (2001), 27(3, May-Jun), 245-59

Effects of different psychological stimuli on oxytocin (OT) and vasopressin (AVP) secretion are reviewed in animals and in humans. The secretion of neuropituitary hormones is also discussed in various ... [more ▼]

Effects of different psychological stimuli on oxytocin (OT) and vasopressin (AVP) secretion are reviewed in animals and in humans. The secretion of neuropituitary hormones is also discussed in various psychiatric diseases such an anorexia nervosa, bipolar disorder, schizophrenia and obsessive-compulsive disorder. AVP and OT are secreted into the hypophyseal portal circulation by neurons which project from the paraventricular nucleus to the external zone of the median eminence. AVP and OT-containing neurons in the suprachiasmatic and paraventricular nuclei project to limbic areas, including the hippocampus, the subiculum, the ventral nucleus of the amygdala and the nucleus of the diagonal band. Specific AVP receptors which are pharmacologically different from the pressor and antidiuretic AVP receptors have been found in the anterior pituitary. OT receptors have been identified in a variety of forebrain sites. The neurohypophyseal secretion is regulated by the cholinergic muscarinic, histaminergic and beta-adrenergic systems. Stress alters the secretion of one or more of the hypothalamic factors which interact at the pituitary to increase the secretion of ACTH. AVP and OT have been shown to modulate the effect of Corticotropin-Releasing Factor (CRF) on ACTH secretion and appear to play a key role in mediating the ACTH response to stress. Although AVP is a relatively weak secretagogue for ACTH, it markedly potentiates the activity of CRF both in vitro and in vivo. The role of OT is more complex. In vitro, OT stimulates ACTH release at high doses whereas in human it inhibits ACTH secretion at low doses. The type of stressor appear to determine the relative importance of these secretatogues in ACTH response. Several recent studies indicate that psychological stressors display a similar degree of variety of secretagogue release patterns as was found earlier for physical stressors. A bewildering array of technique produces a bewildering array of conclusions. In rats, OT may be an important secretagogue during a novel stimulus, whereas the role for AVP is less clear. Indeed two studies out of ten suggest a stimulating role for AVP. In response to frustration and submission, OT and AVP are secreted. Regarding social isolation, results are difficult to interpret and the role of AVP could be species-dependent. In contrast plasma OT levels do not change. After restraint, ACTH release is primarily mediated by the active increase of OT and AVP does not appear to play a role. When restraint is associated with moderate levels of physical components and during immobilisation, all two secretagogs are involved in the ACTH response. With fear, ACTH response appears to be driven by OT. In humans, one study indicates that high emotionality women increase plasma OT in response to uncontrollable noise. Various neuroendocrine dysregulations have been observed in psychiatric disease. Either an increase or a decrease of the hypothalamic-pituitary-adrenal (HPA) function have been described in several illnesses. Effects of OT appear to be reciprocal to the effects of AVP. OT has been called the "amnestic" neuropeptide due to its capacity to attenuate memory consolidation and retrieval. AVP exhibits a central activating action on mood, memory and selective attention. Underweight patients with anorexia nervosa have abnormally high levels of centrally directed AVP and reduced OT levels. These modifications could enhance the retention of cognitive distortions of aversive consequences of eating. Patients with bipolar disorder show a biphasic secretion of AVP. Depressive episodes are associated with decreased vasopressinergic activity whereas manic episodes involve an increased release. AVP might be responsible for an increased catecholamine activity. In addition, lithium could act as an antagonist to AVP. In schizophrenic patients, studies using the apomorphine stimulation suggest increased oxytoninergic and decreased vasopressinergic functions. These findings are consistent with the beneficial role of AVP on schizophrenic symptoms noted in several trials. The increased OT could be responsible for "positive" symptomatology such as delusions and hallucinations. Obsessive compulsive disorder (OCD) includes a range of cognitive and behavioral disturbances that could be influenced by OT. In animals, several studies have emphasized the role of AVP in promoting repetitive grooming behaviors and maintaining conditioned response to aversive stimuli. In OCD patients, one study have reported that AVP/OT ratio was negatively correlated with symptom severity. However, an independent report found similar AVP concentrations in OC patients without a personal or family history of tic disorder and in normal subjects. Whether these modifications are only a consequence of the central disturbances or whether those peptides could participate in the pathogenesis of these affections remains to be elucidated. [less ▲]

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