{"id":2573,"date":"2017-09-07T12:12:51","date_gmt":"2017-09-07T15:12:51","guid":{"rendered":"http:\/\/en-mol.icb.usp.br\/?page_id=2573"},"modified":"2026-03-14T17:44:59","modified_gmt":"2026-03-14T20:44:59","slug":"4-2-connective-tissue","status":"publish","type":"page","link":"https:\/\/mol-en.icb.usp.br\/index.php\/4-2-connective-tissue\/","title":{"rendered":"4-2 Connective tissue"},"content":{"rendered":"

MAIN FEATURES AND COMPONENTS OF THE CONNECTIVE TISSUE \u2013 2<\/strong><\/p>\n

Cells of the connective tissue<\/strong>
\nThey are usually classified into two populations: resident cells<\/strong> and transient cells<\/strong>.
\nThe resident cells are constant, customary and typical components of several types of connective tissue.
\nThe most common resident cells of the type called connective tissue proper<\/strong> are the fibroblasts, mast cells and mesenchymal cells.
\nOther types and subtypes of connective tissue contain typical resident cells found only in that types , such as the chondrocytes in cartilage, and the osteoblasts and osteocytes in bone.
\nThe resident cells are usually long-lived. When necessary, such as after a loss or if they need to increase their activity during inflammatory or healing processes, their number increases at the expense of mesenchymal stem cells or from progenitor cells that arrive from the hemopoietic bone marrow.<\/p>\n

The transient cells<\/strong>, also called wandering cells<\/strong>, are present in many types of conective tissues but not in all (as in cartilage and bone tissue). They are migratory cells brought by the blood or lymph, exercise important activities in the connective tissue and after some time some of them die or (as the lymphocytes) may return to the blood or lymph. Leukocytes (white blood cells) are part of this group. Most of their activity in defending the body against foreign molecules and microorganisms is carried out in the connective tissue. The presence of these cells in the different connective tissues of the body is variable and depends on chemical signals transmitted by cells (e.g. macrophages, neutrophils), which stimulate them to leave the blood or lymph vessels and accumulate in the connective tissue.<\/p>\n

Extracellular matrix (ECM)<\/strong>
\nThe ECM of the connective tissue is composed mainly by macromolecules produced in the connective tisue, in addition to water, ions, peptides, amino acids, carbohydrates and other small molecules originated from from the blood plasma or lymph.
\nThe macromolecules that constitute the extracellular matrix are proteins, glycoproteins, glycosaminoglycans and proteoglycans, whose molecular composition, quantity and relative proportion may differ in various types of connective tissue and in different locations of the organism.
\nAn important group of ECM proteins is organized in filaments of varying thicknesses and lengths. The thicker filaments, visible under the light microscope, are called connective tissue fibers<\/strong> and constitute part of the fibrillar extracellular matrix<\/strong>.
\nMany of the free macromolecules, as the glycosaminoglycans and proteoglycans, constitute the semi-fluid fundamental extracellular matrix<\/strong> of the connective tissue.
\nSome components of the fundamental matrix are \u200b\u200bnot well preserved during routine preparation of histological sections and do not stain well with routine stains. Therefore, under the microscope some areas of the connective tissue extracellular matrix appear as “empty spaces”. Many of these components can be visualized by other stains and by histochemical or immunohistochemical techniques.<\/p>\n

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MAIN FEATURES AND COMPONENTS OF THE CONNECTIVE TISSUE \u2013 2 Cells of the connective tissue They are usually classified into two populations: resident cells and transient cells. The resident cells are constant, customary and typical components of several types of connective tissue. The most common resident cells of the type called connective tissue proper are […]<\/p>\n","protected":false},"author":2,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-2573","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/mol-en.icb.usp.br\/index.php\/wp-json\/wp\/v2\/pages\/2573","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mol-en.icb.usp.br\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/mol-en.icb.usp.br\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/mol-en.icb.usp.br\/index.php\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/mol-en.icb.usp.br\/index.php\/wp-json\/wp\/v2\/comments?post=2573"}],"version-history":[{"count":30,"href":"https:\/\/mol-en.icb.usp.br\/index.php\/wp-json\/wp\/v2\/pages\/2573\/revisions"}],"predecessor-version":[{"id":20891,"href":"https:\/\/mol-en.icb.usp.br\/index.php\/wp-json\/wp\/v2\/pages\/2573\/revisions\/20891"}],"wp:attachment":[{"href":"https:\/\/mol-en.icb.usp.br\/index.php\/wp-json\/wp\/v2\/media?parent=2573"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}