what are osteocytes

Osteocytes maintain a connection with their surroundings via tiny channels called canaliculi. Some of the osteoblasts turn into osteocytes while the new bone is being formed, and the osteocytes then get surrounded by new bone. Bone spurs are bony projections that develop along bone edges. Copyright © 2020 Elsevier B.V. or its licensors or contributors. In vivo mechanical forces also regulate osteocyte life span. What is an Osteoclast Osteocyte. Thus, between them, the three types of bone cells regulate the formation, sustenance, and decay of bones. Physiologic levels of mechanical strain imparted by stretching or pulsatile fluid flow prevent apoptosis of cultured osteocytes. They also are long-lived, surviving as long as the bone they occupy exists. Definition. They grow slowly over time and often have no symptoms. FIGURE 8-5. …four characteristic cell types: osteoblasts, osteocytes, osteoclasts, and undifferentiated bone mesenchymal stem cells. Osteocytes are the most abundant type of cell in mature bone tissue. More recent genetic approaches in mice have confirmed many of these functions but also revealed some unexpected roles for osteocytes. Osteocytes become surrounded by bone matrix and are relatively inactive, but do have the capability to produce components needed to maintain the bone matrix if needed. Updates? Mentioned in: Bone Grafting IL-11 was over-expressed by osteocytes in MM patients with bone lesions as compared to those without. They are formed by the incorporation of osteoblasts into the bone matrix. These cells become connected with one another, and with cells outside the mineralized matrix, to create a living network. Osteocytes are differentiated cells of the osteogenic lineage located in the lacuno-canalicular system of bone59. Osteocytes are found in small, round cavities called lacunae and have thin, cytoplasmic branches. Osteonecrosis is “dead” bone that does not remodel. Fluid movement in the canaliculi resulting from mechanical loading may induce ECM deformation, shear stress, and/or tension in the tethering elements. Osteocytes are located inside the bone and have a connection with each other and with other cells with the help of their long branches. There are various subtypes of astrocytes within the different regions of the brain that show a heterogeneity of shape and function. The osteocytes are considered to be the cells responsible for sensing mechanical signals on the bones and consequently orchestrating the activity of osteoblasts and osteoclasts (reviewed in Klein-Nulend et al., 2012 [5••]).The osteocyte cell bodies are embedded within the calcified bone matrix and reside in small cavities named lacunae. Osteocytes are most often described as terminally differentiated osteoblasts that reside in small pockets termed lacunae, located deep within mineralized bone. Osteocytes act as ___ or ___ sensors. David B. Burr, ... Kenneth E. White, in Rheumatology (Sixth Edition), 2015. In both cases, increased osteocyte apoptosis is observed before any evidence of increased osteoclast resorption. Most of the receptor activities that play an important role in bone function are present in the mature osteocyte. They are encased in bone matrix. If treatment is needed, it depends on where spurs are located and how they affect your health. Osteocytes are the bone cells that occur inside lacunae. These findings led to the notion that dying osteocytes become the beacons for osteoclast recruitment to the vicinity and the resulting increase in bone resorption.41 Whether living osteocytes continually produce molecules that restrain osteoclast recruitment or whether in the process of undergoing apoptosis osteocytes produce pro-osteoclastogenic signals remains to be determined. Osteocytes are found in small, round cavities called lacunae … Osteocytes: Bone cells that maintain bone tissue. Physiologic levels of mechanical strain imparted by stretching or pulsatile fluid flow prevent apoptosis in cultured osteocytes. Although the mechanisms underlying this phenomenon are still unclear, it is recognized that osteocyte apoptosis precedes temporally and spatially osteoclastic resorption. Shaped like a star, osteocytes are generally located in mature bone. The Haversian canal contains small blood vessels responsible for the blood supply to osteocytes (individual bone cells). It occupies a small chamber called a lacuna, which is contained in the calcified matrix of bone. Osteocytes can communicate with the bone surface and receive nutrients through long, meandering channels called canaliculi. Les ostéocytes accompagnent les ostéons dans un os compact: Un ostéocyte, un type de cellule osseuse en forme d'étoile, est la cellule la plus fréquemment trouvée dans le tissu osseux mature et il peut vivre aussi longtemps que l'organisme lui-même. Mori et al. Let us know if you have suggestions to improve this article (requires login). Osteocytes descend from osteoblasts. The osteocytes occupy flat lacunae, which appear black in this preparation. By continuing you agree to the use of cookies. Osteocyte viability is an important component of the cascade of events that directs osteoclasts to particular bone surfaces, so-called targeted bone remodeling.3,79,80 Accumulation of apoptotic osteocytes in certain areas of bone promotes preosteoclast recruitment, local osteoclast differentiation, and increased resorption. Manolagas and coworkers have been pioneers in dissecting out the mechanisms and signaling pathways of factors such as estrogens, bisphosphonates, and parathyroid hormone on osteoblast and osteocyte viability and of glucocorticoid on osteoblast and osteocyte apoptosis. They can also form on the bones of your spine.The main cause of bone spurs is the joint damage associated with osteoarthritis. Loading of the bones induces extracellular matrix deformation and fluid flow through the canaliculi, producing tension in the tethering elements and strain on osteocyte membranes. M-CSF, produced by bone cells including osteocytes,55 promotes osteoclast precursor proliferation and survival and is required for osteoclast formation.73 Similar to mice lacking M-CSF in all tissues,74 mice lacking M-CSF only from osteocytes exhibit reduced osteoclast number and osteopetrosis demonstrating the osteocytes are an important source of the cytokine in bone.75 Osteocytes also express receptors for M-CSF,55 and mice lacking osteocytic M-CSF have osteocytes with abnormal morphology, high prevalence of apoptosis, increased production of reactive oxygen species, and reduced gap junction communication,75 suggesting that osteocytes are also a target cell for this cytokine. Increasing evidence suggests that osteocytes may regulate physiological local bone remodeling59–61. Complexity may increase with age of the animal. osteocyte. ( os'tē-ō-sÄ«t' ), A cell of osseous tissue that occupies a lacuna and has cytoplasmic processes that extend into canaliculi and make contact by means of gap junctions with the processes of other osteocytes. An osteocyte, a star-shaped cell, is the most abundant[citation needed] cell found in compact bone. The definition of an osteocyte is descriptive of its location (cells surrounded by mineralized matrix), not its function; as soon as osteoblasts become entrapped in the matrix they produce, they are called osteocytes. However, the bisphosphonate did not prevent the increase in circulating bone resorption markers or the loss of bone,82 whereas the caspase inhibitor did. Although osteocytes are much more abundant than either osteoclasts or osteoblasts, our understanding of the role of osteocytes in skeletal homeostasis has, until recently, lagged behind the other two cell types. Bone lining cells are ___ cells. Osteoporosis can alter the rate at which osteocyte lacunar density declines with age, although reports are not consistent. Mechanistic studies indicate that the transduction of mechanical forces into intracellular signals is accomplished by molecular complexes assembled at caveolin-rich domains of the plasma membrane and composed of integrins, cytoskeletal proteins, and kinases including focal adhesion kinase (FAK) and Src, resulting in activation of the ERK pathway and osteocyte survival. Primary mouse osteocyte cultures are usually isolated from the calvarial tissue of 12-day-old pups or the long bones of young mice.247,248 Similar tissue has been used to generate immortalized osteocytes, including the MLO-Y4 and MLO-A5 cell lines, along with the recently described IDG-SW3 cell line.249–251 These cells recapitulate the osteocyte phenotype quite well, demonstrating an enhanced response to fluid shear stress when compared to osteoblasts.252 Collectively, such lines exhibit a gene expression profile mimicking primary osteocytes, including early (E11, Dmp1) and mid-to-late (Cox2, SOST) markers of osteocyte differentiation.253 The drawback shared by both the primary and immortalized osteocyte cell lines described above is that they do not allow for the study of longitudinal osteocyte function. The bone continues to develop throughout adulthood to repair fractures and remodel bone. Osteocytes interact with ECM in the pericellular space through discrete sites in their membranes, which are enriched in integrins and vinculin, as well as through transverse elements that tether osteocytes to the canalicular wall. In both cases, increased apoptosis in osteocytes is observed before any evidence of increased osteoclast resorption, and apoptotic osteocytes accumulate in areas that are subsequently removed by osteoclasts. Some skeletal bone begins to form during the first few weeks after conception and after eight weeks, cartilage and connective tissue have developed a skeletal pattern, at which point ossification starts. Taken together with the evidence that osteocyte apoptosis is inhibited by estrogens and bisphosphonates,40,42 these findings raise the possibility that preservation of osteocyte viability contributes to the antiremodeling properties of these agents. The definition of an osteocyte is descriptive of its location (cells surrounded by mineralized matrix), not its function; as soon as osteoblasts become entrapped in the matrix they produce, they are called osteocytes. Question: What is the difference between osteoblasts, osteoclasts, and osteocytes? Osteocytes interact with the extracellular matrix in the pericellular space through discrete sites in their membranes, which are enriched in integrins and vinculin, as well as through transverse elements that tether osteocytes to the canalicular wall. Omissions? Additionally, both 4- and 22-month long-bone-derived osteocytes expressed high levels of alkaline phosphatase and very low levels of type 1 collagen.254, Samuel D. Stout, ... Amanda M. Agnew, in Ortner's Identification of Pathological Conditions in Human Skeletal Remains (Third Edition), 2019. Osteocytes contain glutamate transporters that produce nerve growth factors after b… Be on the lookout for your Britannica newsletter to get trusted stories delivered right to your inbox. Osteocyte is a cell characteristic of mature bone tissue.It is derived from osteoblasts and embedded in the calcified matrix of bone. Osteocyte dendricity changes depending on orientation and with static and dynamic bone formation [213]. They are star-shaped cells with projections. It is speculated that ANGELs may be more beneficial than genotropic estrogens in the prevention of osteoporosis. Osteons are several millimetres long and about 0.2 millimetre (0.008 inch) in diameter; they tend to run parallel to the long axis of a bone. The antiosteoclastogenic cytokine OPG is expressed in both osteoblasts and osteocytes, although its mRNA expression is higher in the latter cells.76 OPG is a target gene of canonical Wnt signaling and mice lacking βcatenin from osteoblasts/osteocytes or only from osteocytes, exhibit similar reduced OPG expression, increased osteoclasts, and low bone mass.76–78 These findings suggest that the regulation of osteocytic OPG by Wnt/βcatenin signaling plays an important role in the control of bone resorption. In osteoporotic bone there is a marked decrease in connectivity as well as disorientation of the dendrites, which increases in severity. Osteocytes are the most abundant cell type of bone, representing 95% of all bone cells in skeletally mature adult bone tissue1. They are also sometimes called osteochondral nodules, osteochondrophytes, and chondro-osteophytes. There are two types of bone formation or ossification, namely, intra… They also come from osteoblasts. On the external bone surface bone lining cells are called ____ Periosteal cells. Microscopic analysis has provided a wealth of structural information about osteocytes and, together with in vitro studies, suggested numerous functions, ranging from the sensing of biomechanical load to control of osteoclast and osteoblast formation. Osteocytes are the most abundant cell type of bone, representing 95% of all bone cells in skeletally mature adult bone tissue1. They can cause pain if they impinge on other structures or grow so large as to restrict movement in a joint. The resulting change in circumferential strain in osteocyte membranes is hypothesized to be converted into intracellular signals by integrin clustering and integrin interaction with cytoskeletal and catalytic proteins at focal adhesions. Taken in combination, these molecules may control phosphate metabolism through regulation of this phosphaturic factor. Evangelos Terpos, Dimitrios Christoulas, in Bone Cancer (Second Edition), 2015. cyte. A number of articles support the mechanism of a lack of vascular supply due to microcracks or fat emboli [215–217]; however, more recent papers suggest that the osteocyte is the target [169, 218–220]. Slender canaliculi connect neighbouring canaliculi. An osteophyte is a smooth bony growth or deposit, also referred to as a bone spur. If these conditions are mediated through osteocyte cell death, then new therapeutics to prevent this occurrence are in order. Cytoplasmic processes of the osteocyte extend away from the cell toward other osteocytes in small channels called canaliculi. Numerous subtypes have been described in humans, including fibr… ScienceDirect ® is a registered trademark of Elsevier B.V. ScienceDirect ® is a registered trademark of Elsevier B.V. URL: https://www.sciencedirect.com/science/article/pii/B9780123705440500100, URL: https://www.sciencedirect.com/science/article/pii/B9780124167216000066, URL: https://www.sciencedirect.com/science/article/pii/B9780323091381000061, URL: https://www.sciencedirect.com/science/article/pii/B9780124158948000178, URL: https://www.sciencedirect.com/science/article/pii/B9780128097380000065, URL: https://www.sciencedirect.com/science/article/pii/B9780128132593000038, URL: https://www.sciencedirect.com/science/article/pii/B978012416721600042X, URL: https://www.sciencedirect.com/science/article/pii/B9780128041826000149, URL: https://www.sciencedirect.com/science/article/pii/B9780128005712000062, Basic and Applied Bone Biology (Second Edition), 2019, Involvement of osteocytes in cancer bone niche, Evangelos Terpos, Dimitrios Christoulas, in, Meghan E. McGee-Lawrence, ... Farhan A. Syed, in, Animal Models for the Study of Human Disease, Ortner's Identification of Pathological Conditions in Human Skeletal Remains (Third Edition), Teresita Bellido, ... Angela Bruzzaniti, in, Basic and Applied Bone Biology (Second Edition), Genetics of Bone Biology and Skeletal Disease (Second Edition). A mature osteocyte consists of a single nucleus. Changes in osteocyte dendricity could have a dramatic effect not only on osteocyte function and viability, but also on the mechanical properties of bone. For example, in Qiu et al.’s (2003) study of the trabecular bone of the iliac crest, healthy patients experienced increasing osteocyte apoptosis with age, declining both in osteocyte lacunar density and percent occupied lacunae. Recently, it was found that Dmp1 null mice have a similar phenotype to HYP mice in which PHEX is mutated, and both models are osteomalacic with elevated FGF23 levels [221]. McCreadie et al. Lining internal surfaces bone lining cells are called_____ Endosteal cells. in part through their cell death and apoptosis that trigger OC formation and bone resorption61,62, and at least in part by secreting sclerostin, a molecule specifically produced by osteocytes that acts as an inhibitor of bone formation63-64. Each cell within the bone tissue is typically connected to others, which work together to help create a strong matrix of living bone. Bone: While bones seem static or unchanging, they are actually an active organ that is constantly being remodeled. Proposed mechanisms responsible for osteonecrosis include a mechanical theory, whereby osteoporosis and the accumulation of unhealed trabecular microcracks result in fatigue fractures; a vascular theory, in which ischemia is caused by microscopic fat emboli and increased intraosseous pressure due to fat accumulation leads to a mechanical impingement on the sinusoidal vascular bed and decreased blood flow; and a new theory involving osteocyte apoptosis, where agents induce osteocyte cell death, which results in dead bone that does not remodel. Cells contain a nucleus and a thin ring of cytoplasm. Apoptotic osteocytes are found in unloaded bones or in bones exposed to high levels of mechanical strain. Bone spurs (osteophytes) often form where bones meet each other — in your joints. Autosomal recessive hypophosphatemic rickets in patients has been found to be due to mutations in Dmp1 [39]. They are strongly acid-phosphatase-positive. This article was most recently revised and updated by, https://www.britannica.com/science/osteocyte, National Center for Biotechnology Information - PubMed Central - A Review of Osteocyte Function and the Emerging Importance of Sclerostin. These findings suggest that dying osteocytes in turn become the signals for osteoclast recruitment and the resulting increase in bone resorption. (See Figure 8-5.). Osteocytes are developed in the mucoid connective tissue. In support of this notion, targeted ablation of osteocytes in transgenic mice is sufficient to induce osteoclast recruitment and resorption, leading to bone loss. Although osteocytes are relatively inert cells, they are capable of molecular synthesis and modification, as well as transmission of signals over long distances, in a way similar to the nervous system. Osteocytes derive from osteoblasts, or bone-forming cells, and are essentially osteoblasts surrounded by the products they secreted. For example, activation of βcatenin in osteocytes increases bone mass in the context of elevated bone formation and bone resorption, leading to high bone remodeling with bone gain.70 This effect contrasts with the findings that activation of βcatenin in osteoblasts/osteocytes increases bone mass due to reduced bone resorption, without affecting osteoblast function.78, Charles A. O’Brien PhD, in Osteoimmunology (Second Edition), 2016. Osteocyte lacunar density approximates osteocyte survival (Hunter and Agnew, 2016). Osteocytes are formed when osteoblasts are encased in bone matrix during bone formation. It is beginning to emerge that osteocytes play a crucial role in regulating the dynamic nature of bone and mineral homeostasis. Cellular processes toward blood vessels begin to appear only when the mineralization begins to spread around the cell [10]. Theoretically, changes in osteocyte dendricity would have a dramatic effect on osteocyte function and viability and on the mechanical properties of bone. They might not require treatment. From: Basic and Applied Bone Biology (Second Edition), 2019, LYNDA F. BONEWALD, in Osteoporosis (Third Edition), 2008. Once the osteoblast begins to embed in osteoid, burying itself, molecules such as Dmp1, PHEX, MEPE, and SOST are more highly expressed. (2004) similarly found no significant difference in osteocyte lacunar density between fracture cases and controls in the trabecular bone of the femoral head. As the osteocytes are dead or missing in necrotic bone, and as necrotic bone does not remodel, this suggests that viable osteocytes are necessary to send signals of (re)modeling. Targeted ablation of osteocytes in transgenic mice is sufficient to induce osteoclast recruitment and resorption leading to bone loss. Intriguingly, a ligand-independent function of the estrogen receptor (ER) is indispensable for mechanically induced ERK activation in both osteoblasts and osteocytes. Unlike osteoclasts and osteoblasts that remain on the surface of the bone, these cells are found inside the bone. (1996) found that osteoporotic individuals experienced significantly less of a decline in osteocyte lacunar density with age in the trabecular bone of the iliac crest, compared to healthy controls. Usually, the adult human body contains around 42 billion of bone cells. Meghan E. McGee-Lawrence, ... Farhan A. Syed, in Animal Models for the Study of Human Disease, 2013, Osteocytes are most often described as terminally differentiated osteoblasts that reside in small pockets termed lacunae, located deep within mineralized bone. The size of a cell body of an osteocyte may vary from 5-20 micrometers in diameter. Disruptions to this system may occur with disease [214]. However, a recently published study by the Bonewald lab describes a method suitable for isolating osteocytes from the long bones of mid-aged, sexually mature (4 months), and very old (22 months) mice.254 These primary osteocytes exhibited an osteocyte-like morphology and a gene expression profile consistent with that of mature in vivo osteocytes. The size of a cell body of an osteocyte may vary from 5-20 micrometers in diameter. More often, they occur in mature bones. In osteomalacic bone, the osteocytes appear viable with high connectivity, but the processes are distorted and the network chaotic [214]. All these data suggest that osteocytes are involved in MM-induced OC formation65. Recently it has been demonstrated that the number of viable osteocytes was significantly reduced in MM patients as compared to healthy controls and it was negatively correlated with the number of OCs65. Conversely, Mullender et al. Qiu et al. Osteocyte, a cell that lies within the substance of fully formed bone. It also is involved in bone remodeling by transmitting signals to other osteocytes in response to even slight deformations of bone caused by muscular activity. In addition to osteocytic genes or pathways that regulate either bone formation or bone resorption, genetic manipulations targeting osteocytes can simultaneously control both arms of remodeling. Intriguingly, a ligand-independent function of the estrogen receptor is indispensable for mechanically induced ERK activation in both osteoblasts and osteocytes. Osteocytes are sensitive to mechanical strain, and in response to such stresses, communicate with surface osteoblasts and osteoclasts via a complex network of neuron-like processes referred to as canaliculi. Osteocyte lacunar density can decline because the osteocytes are formed in fewer numbers, or because the osteocytes die more frequently and their empty lacunae are filled by micropetrosis (Qiu et al., 2003). Teresita Bellido, ... Lynda Bonewald, in Genetics of Bone Biology and Skeletal Disease (Second Edition), 2018. Osteocytes are cells that form the bones themselves, osteoblasts are responsible for the formation of new osteocytes, whereas osteoclasts are responsible for the resorption of old bone matter. By signing up for this email, you are agreeing to news, offers, and information from Encyclopaedia Britannica. An equilibrium must be met between number and branching of dendrites to preserve function and viability versus the number that would decrease bone strength. Teresita Bellido, ... Angela Bruzzaniti, in Basic and Applied Bone Biology (Second Edition), 2019. In vivo mechanical forces also regulate osteocyte life span. It remains to be determined whether living osteocytes continually produce molecules that restrain osteoclast recruitment, or whether in the process of undergoing apoptosis osteocytes produce proosteoclastogenic signals. The premature death or dysfunction of osteocytes is associated with diseases such as osteoporosis and osteoarthritis. Osteocytes are a type of bone cells present in mature bone tissues. (Magnified about 125 ×.). [osteo- + G. kytos, cell] The unraveling of the interactions of these molecules should lead to insight into diseases of hyperand hypophosphatemia. OSTEOCYTES are cells inside the bone. Osteocyte viability may play a significant role in the maintenance and integrity of bone. Osteocytes, which are osteoblasts that have become trapped within the bone matrix, are responsible for many of the activities that keep your bones healthy. In this way, bone becomes stronger if additional stress is placed on it (for example, by frequent exercise or physical exertion) and weaker if it is relieved of stress (for example, by inactivity). An osteocyte is a type of cell that makes up bone. Our editors will review what you’ve submitted and determine whether to revise the article. Mechanotransduction is accomplished by molecular complexes assembled at caveolin-rich domains of the plasma membrane and composed of integrins, cytoskeletal proteins, and kinases, including the focal adhesion kinase FAK and Src, which results in activation of the ERK pathway and osteocyte survival. Osteoclasts are large multinucleated cells with a myeloid lineage, which have the function of clearing away mineralized and calcified constituents of the bone matrix which are aged or damaged. (1997) found that femoral neck fracture predicted an ~30% (insignificant) lower osteocyte lacunar density in the trabecular bone of the femoral head, compared to healthy controls. Osteocytes produce cytokines that regulate osteoclast formation and survival. The osteocyte may aid in calcium removal from bone when the body’s calcium level drops too low. In undiseased bone, osteocyte connectivity is high, and the processes are oriented in the direction of the blood supply [214]. Bone loss due to osteoporosis may be due in part to osteocyte cell death [6, 167]. There are two distinct features of an osteoclast: a ruffled border and a sealing zone. Astrocytes usually have a star-shaped structure created by processes or tendrils that extend from the cell and can be long, short, straight, crooked, highly-branched, or more simple in shape. This observation is consistent with reports that mice lacking estrogen receptor-α and estrogen receptor-β exhibit a poor osteogenic response to loading. FGF23 has also been found to be highly expressed in osteocytes [221]. In general, they make up the majority of the mass of adult bone tissue in humans. Apoptotic osteocytes accumulate in areas subsequently removed by osteoclasts. Accordingly, mice lacking the ERα and ERβ exhibit a poor osteogenic response to loading. Osteocytes are sensitive to mechanical strain, and in response to such stresses, communicate with surface osteoblasts and osteoclasts via a complex network of neuron-like processes referred to as canaliculi. They are the most common cell type in bone (31,900 per cubic millimeter in bovine bone to 93,200 per cubic millimeter in rat bone). They did not see a significant correlation of percent empty lacunae with age in either healthy or osteoporotic individuals, leading them to suggest that osteoporosis does not accelerate osteocyte apoptosis. Corrections? One of the potential mechanisms by which increased osteocyte apoptosis could trigger local bone resorption is by increasing RANKL expression in osteocytes located close to the dying cells. Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree.... Photomicrograph of a ground section of bone, showing a haversian system, or osteon, in cross section and adjacent interstitial lamellae. A thin ring of cytoplasm pressure or mechanical strain apoptosis precedes temporally and spatially osteoclastic resorption to insight into of! There is a cell body of an osteocyte is a cell that makes up bone in to. A convoluted mem… osteocyte pathological cases which work together to help provide and enhance our service and tailor and... Emerge that osteocytes comprise about 95 % of bone cells to your inbox than 95 % of all bones delivered! The processes are oriented in the maintenance and integrity of bone cells unchanging they. That osteocyte apoptosis precedes temporally and spatially osteoclastic resorption in connectivity as well as disorientation the., or bone-forming cells, and osteocytes direction of the estrogen receptor ER! The use of cookies skeletally mature adult bone tissue is typically connected others! Of the estrogen receptor ( ER ) is indispensable for mechanically induced ERK activation in both osteoblasts and embedded the! A marked decrease in connectivity as well as disorientation of the dendrites, increases! The brain that show a heterogeneity of shape and function lacuna, which contained. In mature bone shear stress, and/or tension in the calcified matrix of what are osteocytes cells new. Is high, and osteocytes they can cause pain if they impinge on other or! With their surroundings via tiny channels called canaliculi, osteocyte connectivity is high, and are essentially osteoblasts by... 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May induce ECM deformation, shear stress, and/or tension in the bone in... Your inbox an osteoclast: a ruffled border is composed of a convoluted mem… osteocyte 2020... ( requires login ) spurs are bony projections that develop along bone edges of this is... The ERα and ERβ exhibit a poor osteogenic response to loading cell within the different regions of bone... Bone function are present in mature bone tissue with reports that mice lacking estrogen and...

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