Substance grise périaqueducale

Résumé

thumb|Coupe du colliculus supérieur montrant la voie du nerf oculomoteur. La substance grise périaqueducale est la zone grise à la périphérie de l'aqueduc cérébral. thumb|Section transversale à travers le mésencéphale. 1 Citerne quadrigéminale ; 2 Aqueduc du mésencéphale ; 3 Substance grise périaqueducale ; 4 Citerne interpédonculaire ; 5 Sillon latéral ; 6 Substantia nigra ; 7 Noyau rouge du tegmentum ; 8 Nerf oculomoteur, avec 8’, son noyau d'origine a Lemnisque (en bleu) avec a’ le lemnisque médian et a" le lemnisque latéral ; b Fasciculus longitudinal médial ; c Raphé ; d Fibres temporopontiques ; e Partie du lemnisque médian, Qui se dirige vers le noyau lenticulaire et l'insula ; f Fibres cérébrospinales ; g Fibres fronto-pontiques. La substance grise périaqueducale (PAG) désigne un ensemble de neurones formant une masse de substance grise localisée autour de l'aqueduc cérébral au sein du tegmentum du mésencéphale. Elle joue un rôle important dans la douleur et les comportements

Source officielle

https://fr.wikipedia.org/wiki/Substance_grise_p%C3%A9riaqueducale

À propos de ce résultat

Cette page est générée automatiquement et peut contenir des informations qui ne sont pas correctes, complètes, à jour ou pertinentes par rapport à votre recherche. Il en va de même pour toutes les autres pages de ce site. Veillez à vérifier les informations auprès des sources officielles de l'EPFL.

Publications associées (5)

Publications associées

Chargement

Personnes associées

Chargement

Unités associées

Chargement

Concepts associés (18)

Concepts associés

Chargement

Cours associés (1)

Cours associés

Chargement

Séances de cours associées (6)

Séances de cours associées

Chargement

Altered functional magnetic resonance imaging resting-state connectivity in periaqueductal gray networks in migraine

Nouchine Hadjikhani

Objective: The periaqueductal gray matter (PAG), a known modulator of somatic pain transmission, shows evidence of interictal functional and structural abnormalities in migraineurs, which may contribute to hyperexcitability along spinal and trigeminal nociceptive pathways, and lead to the migraine attack. The aim of this study was to examine functional connectivity of the PAG in migraine.

2011

Chargement

Tonic pain alters functional connectivity of the descending pain modulatory network involving amygdala, periaqueductal gray, parabrachial nucleus and anterior cingulate cortex

Anne-Christine Schmid

Introduction: Resting state functional connectivity (FC) is widely used to assess functional brain alterations in patients with chronic pain. However, reports of FC accompanying tonic pain in pain-free persons are rare. A network we term the Descending Pain Modulatory Network (DPMN) is implicated in healthy and pathologic pain modulation. Here, we evaluate the effect of tonic pain on FC of specific nodes of this network: anterior cingulate cortex (ACC), amygdala (AMYG), periaqueductal gray (PAG), and parabrachial nuclei (PBN). Methods: In 50 pain-free participants (30F), we induced tonic pain using a capsaicin-heat pain model. functional MRI measured resting BOLD signal during pain-free rest with a 32 degrees C thermode and then tonic pain where participants experienced a previously warm temperature combined with capsaicin. We evaluated FC from ACC, AMYG, PAG, and PBN with correlation of self-report pain intensity during both states. We hypothesized tonic pain would diminish FC dyads within the DPMN. Results: Of all hypothesized FC dyads, only PAG and subgenual ACC was weakly altered during pain (F = 3.34; p = 0.074; pain-free>pain d = 0.25). After pain induction sACC-PAG FC became positively correlated with pain intensity (R = 0.38; t = 2.81; p = 0.007). Right PBN-PAG FC during pain-free rest positively correlated with subsequently experienced pain (R = 0.44; t = 3.43; p = 0.001). During pain, this connection's FC was diminished (paired t=-3.17; p = 0.0026). In whole-brain analyses, during pain-free rest, FC between left AMYG and right superior parietal lobule and caudate nucleus were positively correlated with subsequent pain. During pain, FC between left AMYG and right inferior temporal gyrus negatively correlated with pain. Subsequent pain positively correlated with right AMYG FC with right claustrum; right primary visual cortex and right temporo-occipitoparietal junction Conclusion: We demonstrate sACC-PAG tonic pain FC positively correlates with experienced pain and resting right PBN-PAG FC correlates with subsequent pain and is diminished during tonic pain. Finally, we reveal PAG-and right AMYG-anchored networks which correlate with subsequently experienced pain intensity. Our findings suggest specific connectivity patterns within the DPMN at rest are associated with subsequently experienced pain and modulated by tonic pain. These nodes and their functional modulation may reveal new therapeutic targets for neuromodulation or biomarkers to guide interventions.

ACADEMIC PRESS INC ELSEVIER SCIENCE2022

Chargement

This study is part of a long term study on a male rat model of peripubertal stress in the Laboratory of Behavioural Genetics that shows increase aggressive behaviours against their partners. We are using here these rats in order to create a female rat model victim of Intimate Partner Violence during pregnancy and to study the generalisation of fear to all male, that is a symptom of this type of aggression, through behavioural analysis, serotonergic cell activation of the Dorsal Raphe Nucleus (DRN) and activation of other regions known to interact with the DRN such as Periaqueductal Gray (PAG) and Amygdala. This study also reveal an in-utero transmission of aggressive behaviours to the offspring of peripubertally stressed male. Our findings suggest that our model show a generalisation of fear that depends on the type of aggression experienced. This generalisation is mediated by an increase of activation of serotonergic cells of the DRN as well as a general disruption of pattern of activation at the basal level. Interestingly, our results do not show a clear direct link between activation of DRN, PAG and Amygdala during generalisation of fear

2010

Chargement

Tonic pain alters functional connectivity of the descending pain modulatory network involving amygdala, periaqueductal gray, parabrachial nucleus and anterior cingulate cortex

Anne-Christine Schmid

ACADEMIC PRESS INC ELSEVIER SCIENCE2022