<ol><li> Supplement Medien CO 2-unabhängigen Medien mit fötalem Rinderserum, L-Glutamin, Antibiotika und Ascorbinsäure </li><li> Aliquot 40 ml in 50 ml Zentrifugenröhrchen (1 für jede Sehne) </li><li> Aliquot von 10 ml in 15 ml Zentrifugenröhrchen (1 für jede Sehne) </li><li> Sterilisieren chirurgische Instrumente, Autoklaven Blatt, Pinzette und Drehmomentschlüssel in Autoklaven </li><li> Sterilisieren Klemmen und Kraft Mikrometer Tipps durch Einweichen in 70% Ethanol über Nacht </li><li> Ernte Sehnen aus dem hinteren Pfoten des Kaninchens. Kaninchen hätte eingeschläfert nicht mehr als 2 Stunden haben. </li><li> Legen Sehnen in 15 ml Zentrifugenröhrchen mit Medien gefüllt </li><li> Legen Sie eine sterilisierte Autoklaven Blatt in einen sterilen Bereich zu etablieren </li><li> Messen Querschnittsfläche der Sehne <ol style="margin-top: 0in"><li> Legen Sie Mikrometer Tipps Mikrometer, zum korrekten Ausrichten der </li><li> Grip Sehne durch die Enden </li><li> Fit dünnsten Sehne Abschnitt in Nut </li><li> Haben Assistent Ort 50g Gewicht </li><li> Warten Sie 30 Sekunden, lesen Dicke (CSA = Dicke x 1,3) </li></ol></li><li> Legen Sehne wieder in 15 ml Zentrifugenröhrchen </li><li> Wiederholen Sie mit jeder Sehne geladen werden </li><li> Antrieb abbauen von der Basis </li><li> Schneiden Sie zwei 15mm von 40mm-Streifen und einem 3mm von 5mm Stück aus steriler Gaze für jede Sehne </li><li> Roll jeden Streifen verschließen und zwischen den Rillen des distalen Klemme </li><li> Entfernen Sehne vom Zentrifugenröhrchen und Ort an der Klemme, das distale Ende der Sehne am distalen Klemme und den Faserknorpel Region der Sehne am proximalen Klemme </li><li> Legen Sie 3x5 Gaze Stück auf der Oberseite des distalen Ende der Sehne, und befestigen Sie die Klammer </li><li> Sichere proximalen Klemme, wobei sichergestellt Sehne ausgerichtet bleibt zwischen den Klemmen und mit genügend Spielraum, dass es nicht unter Spannung, wenn Klemmen fest angezogen sind. Ziehen Sie Klammern, um 1N-m </li><li> Legen Sie 50ml Zentrifugenröhrchen mit Medien in der Basis </li><li> Legen Antrieb in der Basis </li><li> Wiederholen Sie mit jeder Sehne geladen werden </li><li> Legen Basis über Wasserbad </li><li> Loading-Protokoll <ol style="margin-top: 0in"><li> Voraussetzung Sehnen </li><li> Übernehmen 0,5 N Last, messen Spanngliedlänge (dies ist die Messlänge) </li><li> Bewerben zyklischer Belastung </li></ol></li><li> Antrieb abbauen von der Basis </li><li> Release-Sehne vom Schellen </li><li> Prozess Sehne </li></ol>

<ol>
	<li>Asundi, K., Kursa, K., Lotz, J. C., Rempel, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+system+for+applying+cyclic+loads+to+connective+tissues+under+displacement+or+force+control.">In vitro system for applying cyclic loads to connective tissues under displacement or force control.</a> Ann Biomed Eng. 35, 1188-1195 (2007).</li><li>Asundi, K. R., Rempel, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cyclic+loading+inhibits+expression+of+MMP-3+but+not+MMP-1+in+an+in+vitro+rabbit+flexor+tendon+model.">Cyclic loading inhibits expression of MMP-3 but not MMP-1 in an in vitro rabbit flexor tendon model.</a> Clin Biomech. , .</li><li>Asundi, K. R., Rempel, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=MMP-1,+IL-1&#946;+and+COX-2+mRNA+Expression+is+Modulated+by+Static+Load+in+Rabbit+Flexor+Tendon.">MMP-1, IL-1&#946; and COX-2 mRNA Expression is Modulated by Static Load in Rabbit Flexor Tendon.</a> Ann Biomed Eng. , .</li></ol>

Das Video zeigt ein neues System für die gleichzeitige Laden von bis zu vier Live-Sehnen in Gewebekultur. Typische loading Laufzeiten sind 2 bis 48 Stunden. Nach dem Laden werden die Sehnen entfernt und verarbeitet für die Genexpression. Das System ermöglicht die Untersuchung der Wirkung von Be-Muster auf Veränderungen in Genen, die mit degenerativen Veränderungen in der Sehne verbunden sind. Diese Experimente können einen Einblick in die Mechanismen von Verletzungen mit sich wiederholenden Belastung verbundene Dienstleistungen zu erb...

Custom 4 Linear Actuator Ladesystem warmen Wasserbad 50 ml Röhrchen Sehnen (Kaninchen) Sterile Medien

ex vivo mechanical loading of tendon

Verletzungen der Sehnen (zB Handgelenk Tendinitis, epicondyltis) durch Übernutzung sind in sportlichen Aktivitäten und am Arbeitsplatz verbreitet. Die meisten sind mit gleichbleibend hohe Kraft der Hand-Aktivitäten verbunden. Die Mechanismen der zellulären und strukturellen Schäden aufgrund zyklischer Belastung sind nicht bekannt. Der Zweck dieses Videos ist es, ein neues System, das gleichzeitig geladen werden können vier Sehnen in Gewebekultur zu präsentieren. Das Video beschreibt die Methoden der sterile Gewebe Ernte und wie sich die Sehnen auf ein Spannsystem, die anschließend in Medien eingetaucht und bei 37 ° C geladen Eine Klemme befestigt ist, während der andere mit einem Linearantrieb bewegt wird. Tendon Zugkraft wird mit einer Wägezelle in Serie mit dem mobilen Klammer überwacht. Die Antriebe sind mit einem LabView Programm gesteuert. Die vier Sehnen können wiederholt mit unterschiedlichen Mustern des Ladens, Repetitionsrate, Belastungsgeschwindigkeit und Dauer geladen werden. Loading kann für ein paar Minuten bis 48 Stunden fortgesetzt werden. Am Ende der Belastung sind die Sehnen entfernt, und die Mitte der Substanz für biochemische Analysen extrahiert. Dieses System ermöglicht die Untersuchung der Auswirkungen von Be-Muster auf die Genexpression und strukturellen Veränderungen in der Sehne. Letztlich kann Mechanismen von Verletzungen durch Überbeanspruchung Studien mit den Ergebnissen angewandt zur Behandlung und Prävention sein.

Watch this Scientific Journal Video about Ex vivo Mechanical Loading of Tendon at JoVE.com

Ex vivo Mechanical Loading of Tendon

Ein neues in vitro-System für die gleichzeitige Laden vier Sehnen in der Kultur beschrieben wird.

Ex vivo mechanische Belastung der Sehnen

Injuries to the tendon (e.g., wrist tendonitis, epicondyltis) due to overuse are common in sports activities and the workplace.  Most are associated with ...

Research

JoVE Journal

Biology

9.6K Aufrufe.  University of California, Berkeley. Ein neues in vitro-System für die gleichzeitige Laden vier Sehnen in der Kultur beschrieben wird.

Serie: Ex vivo Mechanical Loading of Tendon

Method for Culture of Early Chick Embryos ex vivo (New Culture)

The chick embryo is a valuable tool in the study of early embryonic development. Its transparency, accessibility and ease of manipulation, make it an ideal tool for studying  the formation and patterning of brain, neural tube, somite and heart primordia. Applications of chick embryo culture include electroporation of DNA or RNA constructs in order to analyze gene function, grafts of growth factor coated beads such as FGFs and BMPs , as well as whole mount in situ hybridization and immunohistochemistry. This video demonstrates the different steps in chick embryo culture; First, the embryo is explanted in saline. Then, the embryo is centered on a glass ring. The membranes surrounding the embryo are lifted along the walls of the ring. The ring is then placed in a culture dish containing a pool of albumine. The culture dish is sealed and placed in a humid chamber, where the embryo is cultured for up to 24 hrs. Finally, the embryo is removed from the ring, fixed and processed for further applications. A troubleshooting guide is also presented.

Method for Culture of Early Chick Embryos ex vivo New Culture

This video demonstrates New culture, a method by which chick embryos are cultured outside the egg for up to 24 hr. This method enables one to study early development (primitive streak to 14 som.), a period corresponding to E7-9 in mouse. Applications of this technique include electroporation, in situ hybridization and immunohistochemistry.

Method for Culture of Early Hühnerembryonen ex vivo (New Culture)

The chick embryo is a valuable tool in the study of early embryonic development. Its transparency, accessibility and ease of manipulation, make it an ...

Forschung

Biologie

An ex-ovo Chicken Embryo Culture System Suitable for Imaging and Microsurgery Applications

Understanding the relationships between genetic and microenvironmental factors that drive normal and malformed embryonic development is fundamental for discovering new therapeutic strategies. Advancements in imaging technology have enabled quantitative investigation of the organization and maturing of the body plan, but later stage embryonic morphogenesis is less clear. Chicken embryos are an attractive vertebrate animal model system for this application because of its ease of culture and surgical manipulation. Early embryos can be cultured for a short time on filter paper rings, which enables complete optical access for cell patterning and fate studies1,2. Studying advanced developmental processes such as cardiac morphogenesis are traditionally performed through a window of the eggshell3-5, but this technique limits optical access due to window size. We previously developed a simple method to culture whole embryos ex-ovo on hexagonal weigh boats for up to 10 days, which enabled high resolution imaging via ultrasonography6,7. These cultures were difficult to transport, limiting the types of imaging tools available for live experiments. We here present an improved shell-less culture system with a cost-effective, portable environmental chamber. Eggs were cracked onto a hammock created by a polyurethane membrane (cling wrap) affixed circumferentially to a plastic cup partially filled with sterile water. The dimensions of the circumference and depth of the hammock were both critical to maintain surface tension, while the mechanics of the hammock and water beneath helped dampen vibrations induced by transportation. A small footprint circulating water bath was also developed to enable continuous temperature control during experimentation. We demonstrate the ability to culture embryos in this way for at least 14 days without morphogenic defect or delay and employ this system in several microsurgical and imaging applications.

An ex-ovo Chicken Embryo Culture System Suitable for Imaging and Microsurgery Applications

In this article, we present a simple methodology to enable long-term ex-ovo avian embryo culture. This technique is ideal for longitudinal experimentation requiring complete optical accessibility and/or sterile transportation in avian embryos.

Ein Ex-ovo Chicken Embryo Culture-System Geeignet für Imaging und Mikrochirurgie Anwendungen

Understanding the relationships between genetic and microenvironmental factors that drive normal and malformed embryonic development is fundamental for ...

Ex Vivo Culture of Primary Human Fallopian Tube Epithelial Cells

Epithelial ovarian cancer is a leading cause of female cancer mortality in the United States. In contrast to other women-specific cancers, like breast and uterine carcinomas, where death rates have fallen in recent years, ovarian cancer cure rates have remained relatively unchanged over the past two decades 1. This is largely due to the lack of appropriate screening tools for detection of early stage disease where surgery and chemotherapy are most effective 2, 3. As a result, most patients present with advanced stage disease and diffuse abdominal involvement. This is further complicated by the fact that ovarian cancer is a heterogeneous disease with multiple histologic subtypes 4, 5. Serous ovarian carcinoma (SOC) is the most common and aggressive subtype and the form most often associated with mutations in the BRCA genes. Current experimental models in this field involve the use of cancer cell lines and mouse models to better understand the initiating genetic events and pathogenesis of disease 6, 7. Recently, the fallopian tube has emerged as a novel site for the origin of SOC, with the fallopian tube (FT) secretory epithelial cell (FTSEC) as the proposed cell of origin 8, 9. There are currently no cell lines or culture systems available to study the FT epithelium or the FTSEC. Here we describe a novel ex vivo culture system where primary human FT epithelial cells are cultured in a manner that preserves their architecture, polarity, immunophenotype, and response to physiologic and genotoxic stressors. This ex vivo model provides a useful tool for the study of SOC, allowing a better understanding of how tumors can arise from this tissue, and the mechanisms involved in tumor initiation and progression.

Ex Vivo Culture of Primary Human Fallopian Tube Epithelial Cells

The fallopian tube (FT) is emerging as an alternative site of origin for serous ovarian carcinoma (SOC). This protocol describes a novel method for the isolation and ex vivo culture of fallopian tube epithelial cells. This system recapitulates the in vivo epithelium and allows the study of SOC pathogenesis.

Ex vivo-Kultur von primären humanen Eileiter Epithelzellen

Epithelial ovarian cancer is a leading cause of female cancer mortality in the United States. In contrast to other women-specific cancers, like breast and ...

A System for ex vivo Culturing of Embryonic Pancreas

The pancreas controls vital functions of our body, including the production of digestive enzymes and regulation of blood sugar levels1. Although in the past decade many studies have contributed to a solid foundation for understanding pancreatic organogenesis, important gaps persist in our knowledge of early pancreas formation2. A complete understanding of these early events will provide insight into the development of this organ, but also into incurable diseases that target the pancreas, such as diabetes or pancreatic cancer. Finally, this information will generate a blueprint for developing cell-replacement therapies in the context of diabetes.
 During embryogenesis, the pancreas originates from distinct embryonic outgrowths of the dorsal and ventral foregut endoderm at embryonic day (E) 9.5 in the mouse embryo3,4. Both outgrowths evaginate into the surrounding mesenchyme as solid epithelial buds, which undergo proliferation, branching and differentiation to generate a fully mature organ2,5,6. Recent evidences have suggested that growth and differentiation of pancreatic cell lineages, including the insulin-producing &beta;-cells, depends on proper tissue-architecture, epithelial remodeling and cell positioning within the branching pancreatic epithelium7,8. However, how branching morphogenesis occurs and is coordinated with proliferation and differentiation in the pancreas is largely unknown. This is in part due to the fact that current knowledge about these developmental processes has relied almost exclusively on analysis of fixed specimens, while morphogenetic events are highly dynamic.
 Here, we report a method for dissecting and culturing mouse embryonic pancreatic buds ex vivo on glass bottom dishes, which allow direct visualization of the developing pancreas (Figure 1). This culture system is ideally devised for confocal laser scanning microscopy and, in particular, live-cell imaging. Pancreatic explants can be prepared not only from wild-type mouse embryos, but also from genetically engineered mouse strains (e.g. transgenic or knockout), allowing real-time studies of mutant phenotypes. Moreover, this ex vivo culture system is valuable to study the effects of chemical compounds on pancreatic development, enabling to obtain quantitative data about proliferation and growth, elongation, branching, tubulogenesis and differentiation. In conclusion, the development of an ex vivo pancreatic explant culture method combined with high-resolution imaging provides a strong platform for observing morphogenetic and differentiation events as they occur within the developing mouse embryo.

A System for ex vivo Culturing of Embryonic Pancreas

Here, we describe a method for isolation, culture and manipulation of mouse embryonic pancreas. This represents an excellent ex vivo system for studying various aspects of pancreatic development, including morphogenesis, differentiation and growth. Pancreatic bud explants can be cultured for several days and used in a range of different applications, including whole-mount immunofluorescence and live imaging.

Ein System für<em&gt; Ex vivo</em&gt; Kultivierung von embryonalen Pankreas

The pancreas controls vital functions of our body,  including the production of digestive enzymes and regulation of blood sugar  levels1. Although in the ...

Ex vivo Culture of Mouse Embryonic Skin and Live-imaging of Melanoblast Migration

Melanoblasts are the neural crest derived precursors of melanocytes; the cells responsible for producing the pigment in skin and hair. Melanoblasts migrate through the epidermis of the embryo where they subsequently colonize the developing hair follicles1,2. Neural crest cell migration is extensively studied in vitro but in vivo methods are still not well developed, especially in mammalian systems. One alternative is to use ex vivo organotypic culture3-6. Culture of mouse embryonic skin requires the maintenance of an air-liquid interface (ALI) across the surface of the tissue3,6. High resolution live-imaging of mouse embryonic skin has been hampered by the lack of a good method that not only maintains this ALI but also allows the culture to be inverted and therefore compatible with short working distance objective lenses and most confocal microscopes. This article describes recent improvements to a method that uses a gas permeable membrane to overcome these problems and allow high-resolution confocal imaging of embryonic skin in ex vivo culture6. By using a melanoblast specific Cre-recombinase expressing mouse line combined with the R26YFPR reporter line we are able to fluorescently label the melanoblast population within these skin cultures. The technique allows live-imaging of melanoblasts and observation of their behavior and interactions with the tissue in which they develop. Representative results are included to demonstrate the capability to live-image 6&#160;cultures in parallel.

Ex vivo Culture of Mouse Embryonic Skin and Live-imaging of Melanoblast Migration

We describe the dissection and ex vivo culture of mouse embryonic skin. The culture system maintains an air-liquid interface across the tissue surface and allows imaging on an inverted microscope. Melanoblasts, a component of the developing skin, are fluorescently labeled allowing their behavior to be observed using confocal microscopy.

Ex-vivo-Kultur von embryonalen Maus-Haut-und-Live-Darstellung von Migration Melanoblasten

Melanoblasts are the neural crest derived precursors of melanocytes; the cells responsible for producing the pigment in skin and hair. Melanoblasts ...

An Ex vivo Culture System to Study Thyroid Development

The thyroid is a bilobated endocrine gland localized at the base of the neck, producing the thyroid hormones T3, T4, and calcitonin. T3 and T4 are produced by differentiated thyrocytes, organized in closed spheres called follicles, while calcitonin is synthesized by C-cells, interspersed in between the follicles and a dense network of blood capillaries. Although adult thyroid architecture and functions have been extensively described and studied, the formation of the &#8220;angio-follicular&#8221; units, the distribution of C-cells in the parenchyma and the paracrine communications between epithelial and endothelial cells is far from being understood.
This method describes the sequential steps of mouse embryonic thyroid anlagen dissection and its culture on semiporous filters or on microscopy plastic slides. Within a period of four days, this culture system faithfully recapitulates in vivo thyroid development. Indeed, (i) bilobation of the organ occurs (for e12.5 explants), (ii) thyrocytes precursors organize into follicles and polarize, (iii) thyrocytes and C-cells differentiate, and (iv) endothelial cells present in the microdissected tissue proliferate, migrate into the thyroid lobes, and closely associate with the epithelial cells, as they do in vivo.
Thyroid tissues can be obtained from wild type, knockout or fluorescent transgenic embryos. Moreover, explants culture can be manipulated by addition of inhibitors, blocking antibodies, growth factors, or even cells or conditioned medium. Ex vivo development can be analyzed in real-time, or at any time of the culture by immunostaining and RT-qPCR.
In conclusion, thyroid explant culture combined with downstream whole-mount or on sections imaging and gene expression profiling provides a powerful system for manipulating and studying morphogenetic and differentiation events of thyroid organogenesis.

An Ex vivo Culture System to Study Thyroid Development

This protocol describes dissection of mouse embryonic thyroid anlagen and the culture of explants on semiporous filters or on microscopy plastic slides. This system is ideal to study morphogenetic or differentiation events occurring during thyroid development of wild type or knockout embryos, and is amenable to gain- and loss-of-function experiments.

Ein<em&gt; Ex-vivo-</em&gt; Kultur-System, um Schilddrüsenentwicklungsstudie

The thyroid is a bilobated endocrine gland localized at the base of the neck, producing the thyroid hormones T3, T4, and calcitonin. T3 and T4 are ...

Spatiotemporal Mapping of Motility in Ex Vivo Preparations of the Intestines

Multiple approaches have been used to record and evaluate gastrointestinal motility including: recording changes in muscle tension, intraluminal pressure, and membrane potential. All of these approaches depend on measurement of activity at one or multiple locations along the gut simultaneously which are then interpreted to provide a sense of overall motility patterns. Recently, the development of video recording and spatiotemporal mapping (STmap) techniques have made it possible to observe and analyze complex patterns in ex vivo whole segments of colon and intestine. Once recorded and digitized, video records can be converted to STmaps in which the luminal diameter is converted to grayscale or color [called diameter maps (Dmaps)]. STmaps can provide data on motility direction (i.e., stationary, peristaltic, antiperistaltic), velocity, duration, frequency and strength of contractile motility patterns. Advantages of this approach include: analysis of interaction or simultaneous development of different motility patterns in different regions of the same segment, visualization of motility pattern changes over time, and analysis of how activity in one region influences activity in another region. Video recordings can be replayed with different timescales and analysis parameters so that separate STmaps and motility patterns can be analyzed in more detail. This protocol specifically details the effects of intraluminal fluid distension and intraluminal stimuli that affect motility generation. The use of luminal receptor agonists and antagonists provides mechanistic information on how specific patterns are initiated and how one pattern can be converted into another pattern. The technique is limited by the ability to only measure motility that causes changes in luminal diameter, without providing data on intraluminal pressure changes or muscle tension, and by the generation of artifacts based upon experimental setup; although, analysis methods can account for these issues. When compared to previous techniques the video recording and STmap approach provides a more comprehensive understanding of gastrointestinal motility.

Spatiotemporal Mapping of Motility in Ex Vivo Preparations of the Intestines

Recently available video recording and spatiotemporal mapping (STmap) techniques make it possible to visualize and quantify both propagating and mixing patterns of intestinal motility. The goal of this protocol is to explain the generation and analysis of STmaps using the GastroIntestinal Motility Monitoring (GIMM) system.

Raum-Zeit-Mapping der Motilität in<em&gt; Ex Vivo</em&gt; Vorbereitung des Darms

Multiple approaches have been used to record and evaluate gastrointestinal motility including: recording changes in muscle tension, intraluminal pressure, ...

The c-FOS Protein Immunohistological Detection: A Useful Tool As a Marker of Central Pathways Involved in Specific Physiological Responses In Vivo and Ex Vivo

Many studies seek to identify and map the brain regions involved in specific physiological regulations. The proto-oncogene c-fos, an immediate early gene, is expressed in neurons in response to various stimuli. The protein product can be readily detected with immunohistochemical techniques leading to the use of c-FOS detection to map groups of neurons that display changes in their activity. In this article, we focused on the identification of brainstem neuronal populations involved in the ventilatory adaptation to hypoxia or hypercapnia. Two approaches were described to identify involved neuronal populations in vivo in animals and ex vivo in deafferented brainstem preparations. In vivo, animals were exposed to hypercapnic or hypoxic gas mixtures. Ex vivo, deafferented preparations were superfused with hypoxic or hypercapnic artificial cerebrospinal fluid. In both cases, either control in vivo animals or ex vivo preparations were maintained under normoxic and normocapnic conditions. The comparison of these two approaches allows the determination of the origin of the neuronal activation i.e., peripheral and/or central. In vivo and ex vivo, brainstems were collected, fixed, and sliced into sections. Once sections were prepared, immunohistochemical detection of the c-FOS protein was made in order to identify the brainstem groups of cells activated by hypoxic or hypercapnic stimulations. Labeled cells were counted in brainstem respiratory structures. In comparison to the control condition, hypoxia or hypercapnia increased the number of c-FOS labeled cells in several specific brainstem sites that are thus constitutive of the neuronal pathways involved in the adaptation of the central respiratory drive.

The c-FOS Protein Immunohistological Detection: A Useful Tool As a Marker of Central Pathways Involved in Specific Physiological Responses In Vivo and Ex Vivo

Here, we present a protocol based on c-FOS protein immunohistological detection, a classical technique used for the identification of neuronal populations involved in specific physiological responses in vivo and ex vivo.

Die c-fos-Protein Immunohistologische Nachweis: Ein nützliches Werkzeug als Marker der Mittelwegen beteiligt sind in spezifischen physiologischen Antworten<em&gt; In Vivo</em&gt; und<em&gt; Ex Vivo</em

Many studies seek to identify and map the brain regions involved in specific physiological regulations. The proto-oncogene c-fos, an immediate early gene, ...

Measuring the Stiffness of Ex Vivo Mouse Aortas Using Atomic Force Microscopy

Arterial stiffening is a significant risk factor and biomarker for cardiovascular disease and a hallmark of aging. Atomic force microscopy (AFM) is a versatile analytical tool for characterizing viscoelastic mechanical properties for a variety of materials ranging from hard (plastic, glass, metal, etc.) surfaces to cells on any substrate. It has been widely used to measure the stiffness of cells, but less frequently used to measure the stiffness of aortas. In this paper, we will describe the procedures for using AFM in contact mode to measure the ex vivo elastic modulus of unloaded mouse arteries. We describe our procedure for isolation of mouse aortas, and then provide detailed information for the AFM analysis. This includes step-by-step instructions for alignment of the laser beam, calibration of the spring constant and deflection sensitivity of the AFM probe, and acquisition of force curves. We also provide a detailed protocol for data analysis of the force curves.

Measuring the Stiffness of Ex Vivo Mouse Aortas Using Atomic Force Microscopy

We present detailed protocols for isolation of aortas from mouse and measurement of their elastic modulus using atomic force microscopy.

Messung der Steifigkeit von<em&gt; Ex Vivo</em&gt; Maus Aorten Mit Rasterkraftmikroskopie

Arterial stiffening is a significant risk factor and biomarker for cardiovascular disease and a hallmark of aging. Atomic force microscopy (AFM) is a ...

Isolation of Retinal Arterioles for Ex Vivo Cell Physiology Studies

The retina is a highly metabolically active tissue that requires a substantial blood supply. The retinal circulation supports the inner retina, while the choroidal vessels supply the photoreceptors. Alterations in retinal perfusion contribute to numerous sight-threatening disorders, including diabetic retinopathy, glaucoma and retinal branch vein occlusions. Understanding the molecular mechanisms involved in the control of blood flow through the retina and how these are altered during ocular disease could lead to the identification of new targets for the treatment of these conditions. Retinal arterioles are the main resistance vessels of the retina, and consequently, play a key role in regulating retinal hemodynamics through changes in luminal diameter. In recent years, we have developed methods for isolating arterioles from the rat retina which are suitable for a wide range of applications including cell physiology studies. This preparation has already begun to yield new insights into how blood flow is controlled in the retina and has allowed us to identify some of the key changes that occur during ocular disease. In this article, we describe methods for the isolation of rat retinal arterioles and include protocols for their use in patch-clamp electrophysiology, calcium imaging and pressure myography studies. These vessels are also amenable for use in PCR-, western blotting- and immunohistochemistry-based studies.

Isolation of Retinal Arterioles for Ex Vivo Cell Physiology Studies

This manuscript describes a straightforward protocol for the isolation of arterioles from the rat retina that can be used in electrophysiological, calcium imaging and pressure myography studies.

Isolierung der retinalen Arteriolen für Ex Vivo Zelle Physiologie Studien

The retina is a highly metabolically active tissue that requires a substantial blood supply. The retinal circulation supports the inner retina, while the ...