![\"Quel](\"\/documents\/images\/histologie_articles\/branchie\/roussette_branchie_145_27-WEB.jpg\")
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Voir l’image de plus grande taille<\/a><\/p>\n <\/p>\n Voir l’image l\u00e9gend\u00e9e<\/a><\/p>\n <\/p>\n L’image de la semaine 32-2019 est issue de l’observation d’une coupe histologique \u00e0 l’objectif x40 du microscope photonique.<\/p>\n Elle comporte principalement des structures fibreuses, compactes en haut \u00e0 gauche et moins denses au centre. De volumineuses masses ovales sont \u00e9galement pr\u00e9sentes \u00e0 droite.<\/p>\n <\/p>\n Les masses ovales de droite apparaissent clairement d\u00e9limit\u00e9es. Elles contiennent chacune une unit\u00e9 circulaire et granuleuse comportant une tache homog\u00e8ne intens\u00e9ment color\u00e9e. Le milieu l’entourant est finement granuleux.<\/p>\n Une telle organisation est caract\u00e9ristique des <\/a>cellules<\/a> animales. La limite cellulaire externe borde une masse de cytoplasme<\/a> contenant de fins granules<\/a>, dans laquelle baigne un noyau tachet\u00e9 muni d’un nucl\u00e9ole.<\/p>\n <\/p>\n Les structures fibreuses centrales sont relativement volumineuses. Allong\u00e9es lorsqu’elles sont coup\u00e9es longitudinalement et circulaires quand elles sont sectionn\u00e9es transversalement, elles poss\u00e8dent un contenu h\u00e9t\u00e9rog\u00e8ne et semblant vacuolis\u00e9 mais sont d\u00e9pourvues de noyau. Elles apparaissent isol\u00e9es les unes des autres par un tissu fibreux l\u00e2che englobant des cellules \u00e0 petits noyaux ovales.<\/p>\n <\/p>\n La r\u00e9gion fibreuse de gauche contient des noyaux plats entour\u00e9s d’une fine couche de cytoplasme. Ils mat\u00e9rialisent la pr\u00e9sence de cellules allong\u00e9es et de taille r\u00e9duite, isol\u00e9es les unes des autres par du mat\u00e9riel extracellulaire<\/a> form\u00e9 de faisceaux<\/a> de fibres.<\/p>\n Cet agencement est rencontr\u00e9 dans le tissu conjonctif<\/a> fibreux, les cellules correspondant \u00e0 des fibrocytes<\/a> et les fibres \u00e0 du collag\u00e8ne<\/a>.<\/p>\n <\/p>\n La dimension importante des cellules pr\u00e9sentes \u00e0 droite et leur forme sugg\u00e8rent qu’il s’agit de corps cellulaires<\/a> de cellules nerveuses ou neurones, d\u00e9crits dans la rubrique Premiers pas histologiques<\/a> de Codex virtualis. L’image de la semaine 32-2019 repr\u00e9sente une structure contenant des corps cellulaires de neurones et des axones. <\/p>\n Pour en savoir plus, consulter :<\/p>\n • <\/span>les pages Premiers pas histologiques<\/a> de Codex virtualis (adresse : http:\/\/codexvirtualis.fr\/codex\/de-lorganisation-interne\/premiers-pas-histologiques)<\/p>\n • <\/span>Burkitt H.G., Young B., Heath J.W., 1993 \u2013 Histologie fonctionnelle Wheater. Arnette, 408p. Paris<\/p>\n • <\/span>Genten F., Terwinghe E., Danguy A., 2010 – Histologie illustr\u00e9e du poisson. Qu\u00e6, collection Savoir-faire, 505p. Versailles<\/p>\n • <\/span>Heusser S., Dupuy H.G., 2015 \u2013 Atlas biologie animale. Dunod, 220p. Paris<\/p>\n • <\/span>Leake L. D., 1975 \u2013 Comparative histology, an introduction to the microscopic structure of animals. Academic press, 738p. London, New York, San Francisco<\/p>\n • <\/span>Wright D.E., 1973 – The Structure of the gills of the Elasmobranch, Scyliorhinus canicula (L.).<\/a> Zeitschrift f\u00fcr Zellforschung und Mikroskopische Anatomie, 144, 4 : 489-509 (adresse : https:\/\/link.springer.com\/article\/10.1007\/BF00307376) <\/p>\n Une citation \u00ab\u00a0La d\u00e9mocratie dont je suis partisan, c’est celle qui donne \u00e0 tous les m\u00eames chances de r\u00e9ussite, selon la capacit\u00e9 de chacun. Celle que je repousse, c’est celle qui pr\u00e9tend remettre au nombre l’autorit\u00e9 qui appartient au m\u00e9rite.\u00a0\u00bb H. Ford Une image Voir l’image de plus grande taille Voir l’image […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[1],"tags":[55,14,23,22],"class_list":["post-12213","post","type-post","status-publish","format-standard","hentry","category-a-la-une","tag-elasmobranche","tag-histologie","tag-observation","tag-physiologie"],"aioseo_notices":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/codexvirtualis.fr\/codex\/wp-json\/wp\/v2\/posts\/12213","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/codexvirtualis.fr\/codex\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/codexvirtualis.fr\/codex\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/codexvirtualis.fr\/codex\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/codexvirtualis.fr\/codex\/wp-json\/wp\/v2\/comments?post=12213"}],"version-history":[{"count":13,"href":"https:\/\/codexvirtualis.fr\/codex\/wp-json\/wp\/v2\/posts\/12213\/revisions"}],"predecessor-version":[{"id":12286,"href":"https:\/\/codexvirtualis.fr\/codex\/wp-json\/wp\/v2\/posts\/12213\/revisions\/12286"}],"wp:attachment":[{"href":"https:\/\/codexvirtualis.fr\/codex\/wp-json\/wp\/v2\/media?parent=12213"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/codexvirtualis.fr\/codex\/wp-json\/wp\/v2\/categories?post=12213"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/codexvirtualis.fr\/codex\/wp-json\/wp\/v2\/tags?post=12213"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\nLes structures fibreuses centrales correspondent \u00e0 leurs prolongements, en l’occurrence des axones<\/a>. Ils sont associ\u00e9s \u00e0 des cellules gliales<\/a> dont les noyaux sont visibles, vraisemblablement des cellules de Schwann \u00e0 l’origine de la gaine de my\u00e9line entourant les axones.
\nLe tissu fibreux environnant est du tissu conjonctif. Localis\u00e9 autour d’un axone, il est dit endon\u00e8vre<\/a>, autour d’un faisceau d’axones, p\u00e9rin\u00e8vre, et autour d’un nerf, \u00e9pin\u00e8vre<\/a>. <\/p>\n
\nIl s’agit d’un ganglion<\/a> nerveux. Il est situ\u00e9 dans un septum de branchie<\/a> de Roussette, d\u00e9crit dans les articles des semaines 28-2019<\/a> et 29-2019<\/a>. <\/p>\n
\nDOI = 10.1007\/BF00307376<\/a><\/p>\n
\n","protected":false},"excerpt":{"rendered":"