Summary

أجهزة الأغنام الجنين على المدى القريب لالمتغيرات المتعددة تسجيلات غير تخدير المزمنة

Published: October 25, 2015
doi:

Summary

يتم استخدام غير تخدير نموذج الأغنام الجنين المجهزة بشكل مزمن لدراسة التطور الجنيني الإنسان في الصحة والمرض، لأنه يسمح وضع الجراحية وصيانة القسطرة والأقطاب، وأخذ عينات الدم المتكررة، حقن مادة، وتسجيل النشاط bioelectrical، والتصوير الحي. وصفنا الإجراءات اللازمة لإنشاء هذا النموذج.

Abstract

The chronically instrumented pregnant sheep has been used as a model of human fetal development and responses to pathophysiologic stimuli such as endotoxins, bacteria, umbilical cord occlusions, hypoxia and various pharmacological treatments. The life-saving clinical practices of glucocorticoid treatment in fetuses at risk of premature birth and the therapeutic hypothermia have been developed in this model. This is due to the unique amenability of the non-anesthetized fetal sheep to the surgical placement and maintenance of catheters and electrodes, allowing repetitive blood sampling, substance injection, recording of bioelectrical activity, application of electric stimulation and in vivo organ imaging. Here we describe the surgical instrumentation procedure required to achieve a stable chronically instrumented non-anesthetized fetal sheep model including characterization of the post-operative recovery from blood gas, metabolic and inflammation standpoints.

Introduction

مجموعة متنوعة من نماذج حيوانية موجودة لدراسة كل حالات الحمل العادية وللخطر، بما في ذلك القوارض المخبرية، الرئيسيات غير البشرية والمجترات المحلية. 1،2،3،4،5 وقد استخدم الأغنام الحوامل المجهزة بشكل مزمن على نطاق واسع لمدة 50 سنوات نموذج للتنمية والاستجابات الجنينية البشرية للمحفزات الفسيولوجية المرضية مثل lipopolysaccharide في (LPS). 6-10 الآفات بعد التعرض LPS تحاكي بالضبط ما ينظر إليه في الخدج المصابين تلين حول البطينات الدماغية، والذي يرجع إلى ملف تعريف النضج مماثل من كلا النوعين. 11 و 12

كما درست مضاعفات الحمل الأخرى بقدر كبير من التفصيل مثل اكتشاف أن السكرية قبل الولادة تعزيز التنمية الرئة 13-15 وفهم تأثير تقييد النمو داخل الرحم على الجنين 16،17.

هو الاستخدام الواسع النطاق للنموذج الأغنام الجنين يرجع ذلك إلى UNIQرق قابليته من الأغنام الجنين غير تخدير لوضع الجراحية وصيانة القسطرة والأقطاب، مما يتيح اخذ عينات من الدم المتكرر، وتسجيل النشاط bioelectrical، وتطبيق التحفيز الكهربائي وتصوير الدماغ فيفو 18 القياس من الممكن أيضا، وإن كانت أقل استخداما بعد نظرا لتطور العالي لإعداد فضلا عن التكلفة الأولية والصيانة. 19

وعلاوة على ذلك، فإن النموذج الأغنام الجنين هي متعددة للغاية كما العديد من الاختلافات أجهزة ممكنة اعتمادا على مقاييس الفائدة. على سبيل المثال، فمن الممكن أن يسجل أكثر من أيام إلى أسابيع إشارات متعددة المتغيرات في الوقت الحقيقي مثل حركات الجنين في التنفس، ونشاط الدماغ الكهربائي، ردود القلب والأوعية الدموية، والكهربائي، وتدفق الدم الإقليمي لمجموعة من الأجهزة باستخدام مجسات تدفق أو المجهرية، وما إلى ذلك بفضل هذا التنوع، وقد أجريت مجموعة واسعة من الدراسات بما في ذلك تطوير كارداتنظام ovascular 20،21،-hypothalamo الغدة النخامية، الغدة الكظرية (HPA) محور 22، نمو المخ تطوير 23 والنوم الدول ولا سيما 24، وآثار نقص الأكسجة / اختناق 25، انخفاض حرارة الجسم العلاجية 26، التهاب 11/06، مزيج من الاثنين معا 27، السكرية 28،29، عقاقير مضادة للاكتئاب 30، وخلل التنسج القصبية الرئوية، (برميل يوميا) 31،32 والبرمجة الجنينية 33،34،35،36،37،38،39 أو تطوير طرائق مراقبة الجنين الرواية قبل وأثناء المخاض وهذا غيض من مناطق قليلة من التحقيق. 40،41،42،43

الهدف العام المتمثل في طريقة عرض لإظهار تنفيذ هذا النموذج تنوعا الأساسي. لأنها تتيح إنشاء مجموعة متنوعة واسعة من البروتوكولات التجريبية الحادة والمزمنة دراسة علم وظائف الأعضاء الجنين والفيزيولوجيا المرضية على التكاملي، جهاز الخلوية والجزيئية المستويات.

Protocol

وجاءت رعاية الحيوان المبادئ التوجيهية للمجلس الكندي للرعاية الحيوان وموافقة مجلس دي مونتريال جامعة على رعاية الحيوان (بروتوكول # 10 ريتش-1560). يتم توفير معلومات مفصلة عن المواد والأساليب المستخدمة في الجدول 1. 1. التخدير <ol style=";text-al…

Representative Results

والمجهزة 38 النعاج مؤرخة الوقت الحوامل في 128 ± 2 أيام من الحمل (DGA، ~ 0.88 الحمل، فترة 145 DGA) مع الشرياني الوريدي والقسطرة الذي يحيط بالجنين والكهربائي (ECG) الأقطاب مع تقنية معقمة تحت التخدير العام (سواء نعجة والجنين ). في حالة الحمل التوأم وقد تم اختيار الجنين أكبر على أساس ال…

Discussion

وقدم التخدير والجراحة المطلوبة لإنشاء نموذج حيواني لدراسة علم وظائف الأعضاء الجنين والفيزيولوجيا المرضية: والأغنام الجنين غير تخدير المجهزة بشكل مزمن.

وينبغي التأكيد على أربع خطوات حاسمة في إطار البروتوكول. أولا، تمرير القسطر?…

Offenlegungen

The authors have nothing to disclose.

Acknowledgements

authors gratefully acknowledge funding support from the Molly Towell Perinatal Research Foundation, Canadian Institutes of Health Research (CIHR), and Fonds de Recherche du Québec – Santé (FRQS) (to MGF) and CIHR-Quebec Training Network in Perinatal Research (QTNPR) (to LDD).

The authors wish to thank Esther Simard, Marco Bosa, Carl Bernard and Carmen Movila for technical assistance.

Materials

ACE Light source Schott-Fostec A20500
Dissecting scissors Fine Science Tools 14060 – 11
Angled dissecting scissors Fine Science Tools 15006 – 09
Scalpel handle Fine Science Tools 10003 – 12 alternating dissecting tool
Curved scalpel blades #12 Fine Science Tools 10012 – 00 alternating dissecting tool
Bone scissors Fine Science Tools 16044 – 10
S & T suture tying forceps Fine Science Tools 00272 – 13
Dumont SS forceps – angled Fine Science Tools 11203 – 25 
Braided silk suture size 6-0 Teleflex Medical 07 – 30  – 10
Medical Tape transpore 3M
Ketamine hydrochloride 100 mg/ml Hospira NDC 0409 – 2051 – 05 Final Does is 80 mg/kg
Tranqui Ved Injection (xylazine 100 mg/ml) Vecdo NDC 50989 – 234 – 11 Final Does is 10 mg/kg
Reactive orange 14 Sigma – Aldrich R – 8254
Ringers Solution Components Solution is gas equilibrated with 95% O2 and 5% Co2, final pH 7.4
Sodium chloride Sigma – Aldrich S7653 Final Concentration: 118 mM
Potassium chloride Fisher Scientific P217 – 3 Final Concentration: 4.7 mM
Calcium chloride dihydrate Fisher Scientific C79 – 500 Final Concentration: 2.5 mM
Potassium phosphate monobasic Fisher Scientific P -285 Final Concentration: 1.2 mM
Magnesium sulfate J.T. Baker Jan-00 Final Concentration: 0.57 mM
4-(2-Hydroxyethyl)piperazine-1-ethanesulfonic acid (HEPES) Fisher Scientific BP 310 – 500 Final Concentration: 5.95 g/L
Glucose Sigma – Aldrich G8270 Final Concentration: 5.5 mM
LifeWindow Digicare Biomedical Technology
CED bioamplifier and ADC units Cambridge Electronic Design Limited,
Unit 4, Science Park,
Milton Road,
Cambridge CB4 0FE
ENGLAND.
Bioamp: 1902; ADC: micro1401; Data acquisition software: Spike 2, V7.13
Neurolog analog signal bioamplifier Digitimer Ltd
37 Hydeway
Welwyn Garden City
Hertfordshire, AL7 3BE, England
NL108A
ABL800Flex Radiometer Canada; 200 Aberdeen Dr, London, ON N5V 4N2
Eppendorf 5804R Eppendorf Canada; 2810 Argentia Road, #2
Mississauga, Ontario, L5N 8L2
Arrow Jugular Catheterization Set Arrow International, Inc., 2400 Bernville Road, Reading, PA 19605 USA
Atravet 10 mg/mL
Diazepam 5mg/mL
Ketamine Ketalar 100 mg/mL
Propofol 10 mg/mL
SurgiVeT Endotracheal Tubes; Smiths Medical ASD, Inc. St. Paul, MN 55112, USA
Cook Airway Exchange Catheter with RAPI-FIT Adapters Cook Critical Care 750, Bloomington IN 47402-0489 USA
Dispomed Ventilator Dispomed Ltd., 745 Nazaire-Laurin, Joliette, Quebec J6E 0L6
BD Insyte-W Becton Dickinson, Infusion Therapy Systems Inc., 9450 S State St, Sandy Utah 84070 USA 22 to 20 G; 1 in [0.9 x 25 mm] to 1.16 in [1.1 x 30 mm]
Edwards Lifesciences Ref: PX272 Pressure monitoring kit with TruWave Disposable Pressure
LifeWindow LW6000 Digicare Biomedical Technology 107 Commerce Road, Boynton Beach, FL 33426-9365 USA
Gaymar
Babcock
Polyvinyl catheters SCI (Scientific Commodities Inc.) 2 meters
2-0 Vicryl
Castroviejo scissors
electrocardiogram (ECG) LIFYY, Metrofunk Kabel-Union, Berlin, Germany four copper electrodes in single sheath, 2 meters
2-O Vicryl
3-0 Vicryl
PDS II USP
Trimethoprim sulfadoxine
Ampicillin
Stopcock Argon Medical, Cat 041220001A Double 4-way Stopcock with male luer lock
Needles Tyco Healthcare 8881202389 Monoject aluminum hub blunt needles, 22Gx, 0.7mmx 38.1mm: for fetal arterial and venous catheters
Needles Tyco Healthcare 8881202322 Monoject aluminum hub blunt needles, 16Gx, 1.6mmx38.1mm: for amniotic catheters

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Burns, P., Liu, H. L., Kuthiala, S., Fecteau, G., Desrochers, A., Durosier, L. D., Cao, M., Frasch, M. G. Instrumentation of Near-term Fetal Sheep for Multivariate Chronic Non-anesthetized Recordings. J. Vis. Exp. (104), e52581, doi:10.3791/52581 (2015).

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