עבודה זו נתמכה על ידי גרנט 5-U24-DK059637-10 למרכז מטבולית עכבר ונדרבילט Phenotyping.

<ol>
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H., Rottman, J. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long+chain+fatty+acid+uptake+in+vivo:+comparison+of+[125I]-BMIPP+and+[3H]-bromopalmitate.">Long chain fatty acid uptake in vivo: comparison of [125I]-BMIPP and [3H]-bromopalmitate.</a> Lipids. 43, 703-711 (2008).</li></ol>

אין ניגודי אינטרסים הכריז.

מהדק hyperinsulinemic-euglycemic, או מהדק האינסולין, הוא שנחשב את &quot;תקן הזהב&quot; שיטה להערכת פעילות האינסולין in vivo. טכניקה זו יושמה כמה מינים כולל בני אדם, כלבים, חולדות ועכברים. בהתחשב במספר גדל והולך של דגמים עכבר מהונדס עבור הפרעות מטבוליות, את המזעור של הטכניקה לשימוש בעכבר סיפקה התקדמות משמעותית למחקר מטבולי. בעוד מושגים מאחורי מהדק את האינסולין הם פשוט, בפועל יש גישות שונות לביצוע ניסויים מהדק אינסולין. זו אינה נקודה טריוויאלית, שכן האופן שבו מתבצע הניסוי משפיע על התוצאות שהושגו 1. כאן אנו מציגים את הפרוטוקול המשמש את MMPC ונדרבילט. ההבדל העיקרי בין פרוטוקול שלנו ושל אחרים היא כי אנו משתמשים קטטר עורקי לקבלת דגימות דם. זאת בניגוד לגישה יותר בשימוש נרחב של obtaining דגימות דם על ידי ניתוק קצה הזנב 4, 7, 11, 12, 14-17. היתרון של דגימה מן קטטר עורקי היא כי הניסוי מתבצע עכבר מודעת מעצורים. דגימה מזנב לעתים קרובות מחייב ריסון עליות במדדי הלחץ כאשר דגימות דם גדולים נרכשים 1. הורמוני סטרס לעורר ייצור גלוקוז אנדוגני ולפגוע סילוק הגלוקוז 18, 19, פוטנציאל לתת את המראה של פנוטיפ עמידות לאינסולין. דגימה מן הזנב ניתק עשויים לדרוש בעלי חיים מיוחדים לטיפול מוסדי ועדת אישור השתמש בגלל האופי שלה מלחיץ. הליך צנתור עורקי פותחה כדי למנוע את הלחץ על העכבר של ניתוק זנב. היבט מרכזי של ביצוע מלחציים אינסולין הוא היכולת לשמור על euglycemia. אין אלגוריתם שיכול לחזות נכונה כיצד Gir צריך להיות מותאם המבוסס על קריאות הסוכר בדם. כמו הניתוח,אנשי מנהלת מהדק ניסויים אינסולין יהפוך בקיאים שמירה euglycemia סביר רק דרך החוויה. חשוב לציין כי בשל שיעור גבוה יותר שלהם מטבולית פי נתוני מחקרים העכבר יהיה רועש מטבעו. זה הופך את המצגת המלאה של הנתונים, כולל קורסי זמן של גלוקוז Gir וערכים מוחלטים אינסולין פלזמה, endoRa, Rd ו - RG מכרעת על היכולת של כל קורא לפרש את התוצאות. שטף גלוקוז גבוה שיעורי העכבר (כ 5 פעמים גבוה יותר מאשר שיעור בבני אדם) צו תדירות גבוהה של גלוקוז הדגימה. בעוד נפח הדם של העכבר מוגבלת, תדר הדגימה המינימלי של אחת כל 10 דקות יש צורך להיות בטוחים כי מהדק הולם הושגה. כפי שניתן לראות בתרשים 4, רמות אינסולין מהדק יכולים להיות שונים בין הקבוצות. גורמים כגון התערבויות דיאטה, מניפולציות מהונדס או הבדלי זנים הרקע יכול להשפיע fasטינג רמות אינסולין, אשר יכולים להשפיע על רמות אינסולין לאחר מכן תפס. פירוש תוצאות כאשר רמות האינסולין מהדק שונים יכולה להיות בעייתית. זה יכול להתייחס באופן ניסיוני על ידי ביצוע ניסויים טייס לבחור עירוי אינסולין כי שיעורי להשיג המקבילה לאינסולין מהדק רמות בין הקבוצות. לחלופין, ניתן להשתמש somatostatin לעכב הפרשת הורמון הלבלב, אינסולין גלוקגון יכול להיות מוחלף בקצב מבוקר בניסוי. גישה זו האחרונה נעשית יותר בדרך כלל מהדק אינסולין מאשר על חולדות ועכברים. אם גישות אלו ניסיוני לא נלקחים, Gir היציב יכול להיות מנורמל רמת אינסולין מהדק, או מדד הרגישות לאינסולין (S I) ניתן לגזור נתונים כמו מהדק שבו S = אני Gir / (G • ΔI), G הוא הריכוז היציב גלוקוז ΔI ההבדל בין אינסולין בצום ריכוזי מהדק. הנחה אחת עם הגישה גם היא כי רמת האינסולין מהדק מושגת היאבטווח שבו הרגישות לאינסולין קשורה באופן ליניארי רמת אינסולין על פי הקבוצה הנחקרת. הנחה זו האחרונה לא תחול כאשר משווים עמידות לאינסולין קבוצות רגישות לאינסולין. באופן אידיאלי, מינון אינסולין עקומת התגובה צריכה להיות שנוצר כדי לבחור את עירוי האינסולין המתאים. עם זאת, בגלל דרישת ניסויים נוספים, זה נעשה לעיתים רחוקות. הרבגוניות מסופק על ידי צנתור עורקי משתרע על גישות ניסיוני מעבר מלחציים euglycemic. לדוגמה, מלחציים hyperglycemic, שבו הגלוקוז הוא החדיר בקצב משתנה כדי לשמור על היפרגליקמיה ביחס גלוקוז בצום, יכול לשמש כדי להעריך את תפקוד הלבלב אנדוגניים 2 vivo, 20, 21. המדידה של הפרשת אינסולין במהלך השלב הראשון במבחן זה מחייב רכישת תכופים של דגימות דם (כלומר כל 2-5 דקות), אשר אינה ישימה כאשר קבלת דגימות מקצה הזנב. יתר על כן,catecholamines גבוהות הנובעות הדגימה הזנב יכול לפגוע הפרשת אינסולין ולהגביר את הפרשת גלוקגון 22. פרוטוקול מהדק אינסולין יכול גם להיות שונה, כדי לאפשר רמות הגלוקוז ליפול היפוגליקמיה יחסית להעריך נגד הרגולציה תגובה 2, 23, 24. צנתור עורקי יכול לשמש גם כדי להעריך את הדינמיקה של חילוף החומרים של הגלוקוז במהלך התרגיל 25-30. זהו יתרון משמעותי על פני גישות קונבנציונליות שנערכו בנקודות זמן יחיד לפני ואחרי אימון או in vivo שרירים בודדים לשעבר. הטכניקות שהוצגו כאן יכול לשמש גם כדי להעריך לא רק הסוכר, אלא גם מטבוליזם חומצות שומן 31.

hyperinsulinemic-euglycemic clamps in conscious, unrestrained mice

סוכרת מסוג 2 מאופיינת על ידי פגם פעילות האינסולין. מהדק hyperinsulinemic-euglycemic, או מהדק האינסולין, הוא שנחשב את &quot;תקן הזהב&quot; שיטה להערכת פעילות האינסולין in vivo. במהלך מהדק אינסולין, hyperinsulinemia מושגת על ידי עירוי אינסולין קבועה. Euglycemia נשמר באמצעות עירוי גלוקוז במקביל בקצב משתנה. גלוקוז זה משתנה קצב עירוי (Gir) נקבעת על ידי מדידת רמת הסוכר בדם בפרקי זמן קצרים במהלך הניסוי והתאמת Gir בהתאם. Gir מעיד על פעולה כל הגוף לאינסולין, כמו עכברים עם פעילות האינסולין משופרת דורשים Gir יותר. מהדק אינסולין יכול לשלב ניהול 2 איזוטופים [14 C] deoxyglucose להעריך רקמה ספציפית ספיגת הגלוקוז [3-3-H] גלוקוז כדי להעריך את היכולת של אינסולין כדי לדכא את קצב הופעת גלוקוז אנדוגני (endoRa), סמן ייצור הגלוקוז בכבד, וכדי לעורר אתקצב היעלמות כל הגוף גלוקוז (Rd). המזעור של מהדק את האינסולין לשימוש במודלים של עכברים גנטי של מחלה מטבולית הוביל להתקדמות משמעותית בחקר הסוכרת. שיטות לביצוע מלחציים אינסולין להשתנות בין מעבדות. חשוב לציין, כי האופן שבו תפס אינסולין מתבצע יכול להשפיע משמעותית על התוצאות שהושגו. פרסמנו הערכה מקיפה של גישות שונות לביצוע מלחציים האינסולין בעכברים מודע 1, כמו גם הערכה של התגובה המטבולית של ארבעה זנים נפוצים עכבר מולדת באמצעות טכניקות שונות מהדק 2. כאן אנו מציגים פרוטוקול לביצוע מלחציים אינסולין על, עכברים מודע רסן שפותחה על ידי עכבר ונדרבילט מטבולית Phenotyping מרכז (MMPC: כתובת: www.mc.vanderbilt.edu / mmpc). זה כולל תיאור של השיטה עבור להשתיל צנתרים בשימוש במהלך מהדק את האינסולין. פרוטוקול המועסקים על ידיונדרבילט MMPC מנצל 3 ייחודי של שתי קטטר המערכת. אחת מוכנס קטטר לווריד הצוואר של חליטות. קטטר שנייה מוכנס לתוך עורק הצוואר, המאפשר דגימת דם ללא צורך לרסן או להתמודד עם העכבר. טכניקה זו מספקת יתרון משמעותי לשיטה הנפוצה ביותר לקבלת דגימות דם במהלך מהדק אינסולין המהווה מדגם מקצה הכרות של הזנב. בניגוד לשיטה זו האחרונה, דגימה מן קטטר עורקי לא מלחיץ את העכבר 1. כמו כן, אנו מתארים את שיטות באמצעות חליטות נותב איזוטופי להעריך רקמות ספציפיות פעילות האינסולין. כמו כן אנו מספקים הנחיות במצגת המתאימה לתוצאות שהתקבלו מלחציים אינסולין.

Watch this Scientific Journal Video about Hyperinsulinemic-euglycemic Clamps in Conscious, Unrestrained Mice at JoVE.com

Hyperinsulinemic-euglycemic Clamps in Conscious, Unrestrained Mice

מהדק hyperinsulinemic-euglycemic, או מהדק אינסולין, הוא תקן הזהב להערכת פעילות האינסולין<em&gt; In vivo</em&gt;. שיטה לביצוע מלחציים האינסולין בעכברים מתואר. זה כולל שיטת צנתור עורקי המאפשר ניסויים להתבצע, עכברים מודע מעצורים עם מתח מינימלי.

Hyperinsulinemic-euglycemic Clamps ב, עכברים מודעת בלתי מרוסנת

Type 2 diabetes is characterized by a defect in insulin action. The hyperinsulinemic-euglycemic clamp, or insulin clamp, is widely considered the "gold ...

hyperinsulinemic-euglycemic-clamps-in-conscious-unrestrained-mice

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94.1K Views.  Sanford-Burnham Medical Research Institute at Lake Nona. מהדק hyperinsulinemic-euglycemic, או מהדק אינסולין, הוא תקן הזהב להערכת פעילות האינסולין In vivo. שיטה לביצוע מלחציים האינסולין בעכברים מתואר. זה כולל שיטת צנתור עורקי המאפשר ניסויים להתבצע, עכברים מודע מעצורים עם מתח מינימלי.

Video: Hyperinsulinemic-euglycemic Clamps in Conscious, Unrestrained Mice

Transthoracic Echocardiography in Mice

In recent years, murine models have become the primary avenue for studying the molecular mechanisms of cardiac dysfunction resulting from changes in gene expression. Transgenic and gene targeting methods can be used to generate mice with altered cardiac size and function,1-3 and as a result, in vivo techniques are needed to evaluate their cardiac phenotype. Transthoracic echocardiography, pulse wave Doppler (PWD), and tissue Doppler imaging (TDI) can be used to provide dimensional measurements of the mouse heart and to quantify the degree of cardiac systolic and diastolic performance. Two-dimensional imaging is used to detect abnormal anatomy or movements of the left ventricle, whereas M-mode echo is used for quantification of cardiac dimensions and contractility.4,5 In addition, PWD is used to quantify localized velocity of turbulent flow,6 whereas TDI is used to measure the velocity of myocardial motion.7 Thus, transthoracic echocardiography offers a comprehensive method for the noninvasive evaluation of cardiac function in mice.

Transthoracic echocardiography offers a noninvasive method for the evaluation of cardiac function in mice. A combination of ultrasound and Doppler imaging modalities can be used to obtain dimensional measurements of the heart and intracardiac blood flow, which together provide an assessment of cardiac systolic and diastolic performance.

אקו Transthoracic ב עכברים

In recent years, murine models have become the primary avenue for studying the molecular mechanisms of cardiac dysfunction resulting from changes in gene ...

Hyperinsulinemic-Euglycemic Clamp in the Conscious Rat

Type 2 diabetes (T2D) is rapidly rising in prevalence. Characterized by either inadequate insulin production or the inability to utilize insulin produced, T2D results in elevated blood glucose levels. The "gold-standard" in assessing insulin sensitivity is a hyperinsulinemic-euglycemic clamp or insulin clamp. In this procedure, insulin is infused at a constant rate resulting in a drop in blood glucose. To maintain blood glucose at a constant level, exogenous glucose (D50) is infused into the venous circulation. The amount of glucose infused to maintain homeostasis is indicative of insulin sensitivity. Here, we show the basic clamp procedure in the chronically catheterized, unrestrained, conscious rat. This model allows blood to be collected with minimal stress to the animal. Following the induction of anesthesia, a midline incision is made and the left common carotid artery and right jugular vein are catheterized. Inserted catheters are flushed with heparinized saline, then exteriorized and secured. Animals are allowed to recover for 4-5 days prior to experiments, with weight gain monitored daily. Only those animals who regain weight to pre-surgery levels are used for experiments. On the day of the experiment, rats are fasted and connected to pumps containing insulin and D50. Baseline glucose is assessed from the arterial line and used a benchmark throughout the experiment (euglycemia). Following this, insulin is infused at a constant rate into the venous circulation. To match the drop in blood glucose, D50 is infused. If the rate of D50 infusion is greater than the rate of uptake, a rise in glucose will occur. Similarly, if the rate is insufficient to match whole body glucose uptake, a drop will occur. Titration of glucose continues until stable glucose readings are achieved. Glucose levels and glucose infusion rates during this stable period are recorded and reported. Results provide an index of whole body insulin sensitivity. The technique can be refined to meet specific experimental requirements. It is further enhanced by the use of radioactive tracers that can determine tissue specific insulin-stimulated glucose uptake as well as whole body glucose turnover.

The hyperinsulinemic-euglycemic clamp is the "gold standard" for the assessment of insulin action. Insulin is infused at a constant rate stimulating glucose uptake. The amount of exogenous glucose infused to counter this drop is indicative of insulin sensitivity. Here the procedure is performed on a conscious, unrestrained rat.

Hyperinsulinemic-Euglycemic קלאמפ של עכברוש המודע

Type 2 diabetes (T2D) is rapidly rising in prevalence. Characterized by either inadequate insulin production or the inability to utilize insulin produced, ...

Controlled Cervical Laceration Injury in Mice

Use of genetically modified mice enhances our understanding of molecular mechanisms underlying several neurological disorders such as a spinal cord injury (SCI). Freehand manual control used to produce a laceration model of SCI creates inconsistent injuries often associated with a crush or contusion component and, therefore, a novel technique was developed. Our model of cervical laceration SCI has resolved inherent difficulties with the freehand method by incorporating 1) cervical vertebral stabilization by vertebral facet fixation, 2) enhanced spinal cord exposure, and 3) creation of a reproducible laceration of the spinal cord using an oscillating blade with an accuracy of &plusmn;0.01 mm in depth without associated contusion. Compared to the standard methods of creating a SCI laceration such as freehand use of a scalpel or scissors, our method has produced a consistent lesion. This method is useful for studies on axonal regeneration of corticospinal, rubrospinal, and dorsal ascending tracts.

A novel technique to create a reproducible in vivo model of cervical spinal cord laceration injury in the mouse is described. This technique is based on spine stabilization by fixation of the cervical facets and laceration of the spinal cord using an oscillating blade with an accuracy of &plusmn;0.01 mm.

פגיעה קריעת צוואר הרחם מבוקרת בעכברים

Use of genetically modified mice enhances our  understanding of molecular mechanisms underlying several neurological disorders  such as a spinal cord ...

Carotid Artery Infusions for Pharmacokinetic and Pharmacodynamic Analysis of Taxanes in Mice

When proposing the use of a drug, drug combination, or drug delivery into a novel system, one must assess the pharmacokinetics of the drug in the study model. As the use of mouse models are often a vital step in preclinical drug discovery and drug development1-8, it is necessary to design a system to introduce drugs into mice in a uniform, reproducible manner. Ideally, the system should permit the collection of blood samples at regular intervals over a set time course. The ability to measure drug concentrations by mass-spectrometry, has allowed investigators to follow the changes in plasma drug levels over time in individual mice1, 9, 10. In this study, paclitaxel was introduced into transgenic mice as a continuous arterial infusion over three hours, while blood samples were simultaneously taken by retro-orbital bleeds at set time points. Carotid artery infusions are a potential alternative to jugular vein infusions, when factors such as mammary tumors or other obstructions make jugular infusions impractical. Using this technique, paclitaxel concentrations in plasma and tissue achieved similar levels as compared to jugular infusion. In this tutorial, we will demonstrate how to successfully catheterize the carotid artery by preparing an optimized catheter for the individual mouse model, then show how to insert and secure the catheter into the mouse carotid artery, thread the end of the catheter out through the back of the mouse&#8217;s neck, and hook the mouse to a pump to deliver a controlled rate of drug influx. Multiple low volume retro-orbital bleeds allow for analysis of plasma drug concentrations over time.

This method was developed with the goal of delivering a steady drug solution via the carotid artery, to assess the pharmacokinetics of novel drugs in mouse models.

חליטות עורק הראשי לpharmacokinetic וpharmacodynamic ניתוח של taxanes בעכברים

When proposing the use of a drug, drug combination, or drug delivery into a novel system, one must assess the pharmacokinetics of the drug in the study ...

Heterotopic Cervical Heart Transplantation in Mice

The heterotopic cervical heart transplantation in mice is a valuable tool in transplant and cardiovascular research. The cuff technique greatly simplifies this model by avoiding challenging suture anastomoses of small vessels thereby reducing warm ischemia time. In comparison to abdominal graft implantation the cervical model is less invasive and the implanted graft is easily accessible for further follow-up examinations. Anastomoses are performed by pulling the ascending aorta of the graft over the cuff with the recipient&#8217;s common carotid artery and by pulling the main pulmonary artery over the cuff with the external jugular vein. Selection of appropriate cuff size and complete mobilization of the vessels are important for successful revascularization. Ischemia-reperfusion (I/R) injury can be minimized by perfusing the graft with a cardioplegic solution and by hypothermia. In this article, we provide technical details for a simplified and improved cuff technique, which should allow surgeons with basic microsurgical skills to perform the procedure with a high success rate.

The cuff technique shortens and facilitates the model of heterotopic cervical heart transplantation in mice by avoiding technically challenging suture anastomoses of small vessels. The technical details shown in this video paper should allow researches to establish this model in their laboratories.

Heterotopic צוואר הרחם לב השתלה בעכברים

The heterotopic cervical heart transplantation in mice is a valuable tool in transplant and cardiovascular research. The cuff technique greatly simplifies ...

Transcutaneous Assessment of Renal Function in Conscious Rodents

Glomerular filtration rate (GFR) is the gold standard to assess overall kidney function. However, traditional methods to evaluate GFR are cumbersome and time-consuming. In addition, serial blood or urine samples are required, with the associated stress for the experimental animals. A recent technique significantly reduces the investment in time and resources, minimizing the invasiveness and the animal stress, but being equally valid as the traditional approaches. The method measures transcutaneously renal function. Using an optical device and the exogenous renal marker fluorescein isothiocyanate (FITC)-sinistrin, this technique is capable of measuring the elimination kinetics of the marker through the skin. With neither blood nor urine samples nor the associated laboratory assays needed, the results of the transcutaneous measurement are almost instantaneously available. The method has been already validated in different species and successfully applied in several models of renal pathology. Moreover, due to its minimally invasive characteristics, it is suitable for sequential measurements within the same animal. Here is provided a detailed protocol to carry out the transcutaneous assessment of renal function in rodents.

Determination of glomerular filtration rate (GFR) is the gold standard to assess overall kidney function. However, traditional procedures to measure this parameter are cumbersome and require a large investment of time. Here we describe a faster and minimally invasive method to determinate GFR transcutaneously.

הערכת Transcutaneous של תפקוד כלייתי במכרסמי Conscious

Glomerular filtration rate (GFR) is the gold standard to assess overall kidney function. However, traditional methods to evaluate GFR are cumbersome and ...

Novel Approach for Simultaneous Recording of Renal Sympathetic Nerve Activity and Blood Pressure with Intravenous Infusion in Conscious, Unrestrained Mice.

Renal sympathetic nerves contribute significantly to both physiological and pathophysiological phenomena. Evaluating renal sympathetic nerve activity (RSNA) is of great interest in many areas of research such as chronic kidney disease, hypertension, heart failure, diabetes and obesity. Unequivocal assessment of the role of the sympathetic nervous system is thus imperative for proper interpretation of experimental results and understanding of disease processes. RSNA has been traditionally measured in anesthetized rodents, including mice. However, mice usually exhibit very low systemic blood pressure and hemodynamic instability for several hours during anesthesia and surgery. Meaningful interpretation of RSNA is confounded by this non-physiological state, given the intimate relationship between sympathetic nervous tone and cardiovascular status. To address this limitation of traditional approaches, we developed a new method for measuring RSNA in conscious, freely-moving mice. Mice were chronically instrumented with radio-telemeters for continuous monitoring of blood pressure as well as a jugular venous infusion catheter and custom-designed bipolar electrode for direct recording of RSNA. Following a 48-72 hour recovery period, survival rate was 100% and all mice behaved normally. At this time-point, RSNA was successfully recorded in 80% of mice, with viable signals acquired up to 4 and 5 days post-surgery in 70% and 50% of mice, respectively. Physiological blood pressures were recorded in all mice (116&plusmn;2 mmHg; n=10). Recorded RSNA increased with eating and grooming, as well-established in the literature. Furthermore, RSNA was validated by ganglionic blockade and modulation of blood pressure with pharmacological agents. Herein, an effective and manageable method for clear recording of RSNA in conscious, freely-moving mice is described.

Anesthetized mice exhibit non-physiological systemic blood pressure, which precludes meaningful assessment of autonomic tone given the intimate relationship between blood pressure and the autonomic nervous system. Thus, a novel method to simultaneously record renal sympathetic nerve activity and blood pressure with intravenous infusion in conscious mice is outlined.

בגישה חדשנית עבור הקלטה בו זמנית של פעילות העצבים הסימפתטית כליות, לחץ דם עם עירוי תוך ורידי, בהכרה, עכברים ערככם.

Renal sympathetic nerves contribute significantly to both physiological and pathophysiological phenomena. Evaluating renal sympathetic nerve activity ...

Assessment of Respiratory Function in Conscious Mice by Double-chamber Plethysmography

Air volume changes created by a conscious subject breathing spontaneously within a body box are at the basis of plethysmography, a technique used to non-invasively assess some features of the respiratory function in humans as well as in laboratory animals. The present article focuses on the application of the double-chamber plethysmography (DCP) in small animals. It provides background information on the methodology as well as a detailed step-by-step procedure to successfully assess respiratory function in conscious, spontaneously breathing animals in a non-invasive manner. The DCP can be used to monitor the respiratory function of multiple animals in parallel, as well as to identify changes induced by aerosolized substances over a chosen time period and in a repeated manner. Experiments on control and allergic mice are used herein to demonstrate the utility of the technique, explain the associated outcome parameters, as well as to discuss the related advantages and shortcomings. Overall, the DCP provides valid and theoretically sound readouts that can be trusted to evaluate the respiratory function of conscious small animals both at baseline and after challenges with aerosolized substances.

The objective of the present article is to provide a detailed description of the recommended procedures to evaluate respiratory function in conscious mice by double-chamber plethysmography.

הערכה של תפקוד מערכת הנשימה בעכברים בהכרה על ידי כפול-תא Plethysmography

Air volume changes created by a conscious subject breathing spontaneously within a body box are at the basis of plethysmography, a technique used to ...

Repeated Orotracheal Intubation in Mice

The literature describes several methods for mouse intubation that either require visualization of the glottis through the oral cavity or incision in the ventral neck for direct confirmation of cannula placement in the trachea. The relative difficulty or the tissue trauma induced to the subject by such procedures can be an impediment to an investigator&#8217;s ability to perform longitudinal studies. This article illustrates a technique in which physical manipulation of the mouse following the use of a depilatory to remove hair from the ventral neck permits transcutaneous visualization of the trachea for orotracheal intubation regardless of degree of skin pigmentation. This method is innocuous to the subject and easily achieved with a limited understanding of murine anatomy. This refined approach facilitates repeated intubation, which may be necessary for monitoring progression of disease or instillation of treatments. Using this method may result in a reduction of the number of animals and technical skill required to measure lung function in mouse models of respiratory disease.

The goal of this article is to describe a refined method of intubation of the laboratory mouse. The method is noninvasive and, therefore, ideal for studies that require serial monitoring of respiratory function and/or instillation of treatments into the lung.

וחזר אורוקנה אל בעכברים

The literature describes several methods for mouse intubation that either require visualization of the glottis through the oral cavity or incision in the ...

Implantation of Combined Telemetric ECG and Blood Pressure Transmitters to Determine Spontaneous Baroreflex Sensitivity in Conscious Mice

Blood pressure (BP) and heart rate (HR) are both controlled by the autonomic nervous system (ANS) and are closely intertwined due to reflex mechanisms. The baroreflex is a key homeostatic mechanism to counteract acute, short-term changes in arterial BP and to maintain BP in a relatively narrow physiological range. BP is sensed by baroreceptors located in the aortic arch and carotid sinus. When BP changes, signals are transmitted to the central nervous system and are then communicated to the parasympathetic and sympathetic branches of the autonomic nervous system to adjust HR. A rise in BP causes a reflex decrease in HR, a drop in BP causes a reflex increase in HR.
Baroreflex sensitivity (BRS) is the quantitative relationship between changes in arterial BP and corresponding changes in HR. Cardiovascular diseases are often associated with impaired baroreflex function. In various studies reduced BRS has been reported in e.g., heart failure, myocardial infarction, or coronary artery disease. 
Determination of BRS requires information from both BP and HR, which can be recorded simultaneously using telemetric devices. The surgical procedure is described beginning with the insertion of the pressure sensor into the left carotid artery and positioning of its tip in the aortic arch to monitor arterial pressure followed by the subcutaneous placement of the transmitter and ECG electrodes. We also describe postoperative intensive care and analgesic management. After a two-week period of post-surgery recovery long-term ECG and BP recordings are performed in conscious and unrestrained mice. Finally, we include examples of high-quality recordings and the analysis of spontaneous baroreceptor sensitivity using the sequence method.

The baroreflex is a heart-rate regulation mechanism by the autonomic nervous system in response to blood-pressure changes. We describe a surgical technique to implant telemetry transmitters for continuous and simultaneous measurement of electrocardiogram and blood pressure in mice. This can determine spontaneous baroreflex sensitivity, an important prognostic marker for cardiovascular disease.

השתלת משדרי אק"ג ולחץ דם טלמטריים משולבים לקביעת רגישות ספונטנית לברפלקס בעכברים מודעים

Blood pressure (BP) and heart rate (HR) are both controlled by the autonomic nervous system (ANS) and are closely intertwined due to reflex mechanisms. ...