بتمويل من NSF (0854551).

<ol>
	<li>Lewis, R. S., Hudspeth, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Voltage-+and+ion-dependent+conductances+in+solitary+vertebrate+hair+cells.">Voltage- and ion-dependent conductances in solitary vertebrate hair cells.</a> Nature. 304, 538-5341 (1983).</li><li>Art, J. J., Fettiplace, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Variation+of+membrane+properties+in+hair+cells+isolated+from+the+turtle+cochlea.">Variation of membrane properties in hair cells isolated from the turtle cochlea.</a> J. Physiol. 385, 207-242 (1987).</li><li>Sugihara, I., Furukawa, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Morphological+and+functional+aspects+of+two+different+types+of+hair+cells+in+the+goldfish+sacculus.">Morphological and functional aspects of two different types of hair cells in the goldfish sacculus.</a> J. Neurophysiol. 62, 1330-1343 (1989).</li><li>Lee, S., Briklin, O., Hiel, H., Fuchs, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Calcium-dependent+inactivation+of+calcium+channels+in+cochlear+hair+cells+of+the+chicken.">Calcium-dependent inactivation of calcium channels in cochlear hair cells of the chicken.</a> J. Physiol. 583, 909-922 (2007).</li><li>Horn, R., Marty, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Muscarinic+activation+of+ionic+currents+measured+by+a+new+whole-cell+recording+method.">Muscarinic activation of ionic currents measured by a new whole-cell recording method.</a> J. Gen. Physiol. 92, 145-159 (1988).</li><li>Rae, J. R., Cooper, K., Gates, P., Watsky, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Low+access+perforated+patch+recordings+using+amphotericin+B.">Low access perforated patch recordings using amphotericin B.</a> J. Neurosci. Meth. 37, 15-26 (1991).</li><li>Lumpkin, E. A., Hudspeth, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Detection+of+Ca2++entry+through+mechanosensitive+channels+localizes+the+site+of+mechanoelectrical+transduction+in+hair+cells.">Detection of Ca2+ entry through mechanosensitive channels localizes the site of mechanoelectrical transduction in hair cells.</a> Proc. Natl Acad. Sci. U.S.A. 92, 10297-10301 (1995).</li><li>Liang, J., Burgess, S. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gross+and+fine+dissection+of+inner+ear+sensory+epithelia+in+adult+zebrafish+(Danio+rerio).">Gross and fine dissection of inner ear sensory epithelia in adult zebrafish (Danio rerio).</a> J. Vis Exp. 27, e1211 (2009).</li><li>Hudspeth, A. J., Lewis, R. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Kinetic+analysis+of+voltage-+and+ion-dependent+conductances+in+saccular+hair+cells+of+the+bull-frog,+Rana+catesbeiana.">Kinetic analysis of voltage- and ion-dependent conductances in saccular hair cells of the bull-frog, Rana catesbeiana.</a> J. Physiol. 400, 237-274 (1988).</li><li>Hudspeth, A. J., Lewis, R. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+model+for+electrical+resonance+and+frequency+tuning+in+saccular+hair+cells+of+the+bull-frog,+Rana+catesbeiana.">A model for electrical resonance and frequency tuning in saccular hair cells of the bull-frog, Rana catesbeiana.</a> J. Physiol. 400, 275-297 (1988).</li><li>Parsons, T. D., Lenzi, D., Almer, W., Roberts, W. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Calcium-triggered+exocytosis+in+an+isolated+presynaptic+cell:+capacitance+measurements+in+saccular+hair+cells.">Calcium-triggered exocytosis in an isolated presynaptic cell: capacitance measurements in saccular hair cells.</a> Neuron. 13, 875-883 (1994).</li><li>Kim, M. -. H., Vickers, E., von Gersdorff, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Patch-clamp+capacitance+measurements+and+Ca2++imaging+at+single+nerve+terminals+in+retinal+slices.">Patch-clamp capacitance measurements and Ca2+ imaging at single nerve terminals in retinal slices.</a> J. Vis Exp. 59, e3345 (2012).</li><li>Housley, G. D., Ashmore, J. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+measurement+of+the+action+of+acetylcholine+on+isolated+outer+hair+cells+of+the+guinea+pig+cochlea.">Direct measurement of the action of acetylcholine on isolated outer hair cells of the guinea pig cochlea.</a> Proc. R. Soc. Lond. B. 244, 161-167 (1991).</li><li>Nicolson, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+genetics+of+hearing+and+balance+in+zebrafish.">The genetics of hearing and balance in zebrafish.</a> Ann. Rev. Genetics. 39, 9-22 (2005).</li></ol>

الإعلان عن أي تضارب في المصالح.

تشريح دقيق للأجهزة والعلاج لطيف نهاية الخلايا أمر بالغ الأهمية لنجاح العزلة صحية، سليمة وخلايا الشعر بالموقع الناحية الفسيولوجية. والانضمام إلى النصائح التالية ضمان النجاح: <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> فمن الأسهل للحصول على الخلايا السليمة من الأسماك الصغيرة (2-2.5 سم في الطول). أكبر الأسماك والعديد من قطرات الدهون التي تصور أكثر غامضة أثناء عملية التشريح. </li><li style=";text-align:right;direction:rtl"> يجب توخي الحذر عند إزالة otoliths، الذي علا في خلايا الشعر. تجنب لمس الخلايا عند الاستيلاء على otoliths بالملقط. </li><li style=";text-align:right;direction:rtl"> ويتم الحصول على أفضل النتائج عندما يتم رفع وبقع قبيبات قبالة كما صفائح وخلايا ظهارة من triturated. </li><li style=";text-align:right;direction:rtl"> نجد استخدام الشعر الكلب ليسحن الخلايا لتكون متفوقة على غيرها من الطرق، بما في ذلك استخدام الرموش الإنسان 7 التي ليست مدبب كما وأقل مرونة. </li><li style=";text-align:right;direction:rtl"> خلال التصحيح تحامل، وتطبيق الضغط الايجابي لرانه الكهربائي لأنها تمر من خلال واجهة الهواء / الحل هو المهم للحفاظ على تلميح نظيفة. الافراج عن الضغط الايجابي لتمكين الخلية إلى &quot;القفز&quot; على القطب مهم أيضا. هذا الأسلوب مسح وحدة تخزين صغيرة من الأمفوتريسين المحتوية على الحل بعيدا عن الحافة، مما يزيد من احتمال تشكيل ختم gigaohm مع الخلية. في تجاربنا نحن نستخدم تقنية تسجيل التصحيح ثقب بدلا من تكوين خلية كاملة التقليدية بسبب هشاشة الخلايا. محاولة &quot;الذهاب خلية كاملة&quot; كثيرا ما يؤدي إلى فقدان ختم gigaohm. </li></ol> إن أسلوب الموصوفة هنا تسفر مئات من الخلايا شعر صحي لكل حيوان. لا يمكن أن يؤديها تقنية في درجة حرارة الغرفة ويتطلب أي معدات خاصة بعد تشريح المجهر. وكان تقرير سابق إن الرب في وصف تشريح الأذن الداخلية في الزرد باستخدام نهج بطني 8. هؤلاء المؤلفين تبين dissection من كله، بارافورمالدهيد الثابتة أجهزة الأذن الداخلية. نحن نشجع القارئ لمشاهدة هذا الفيديو للمقارنة بين الطرق التي نستخدمها. ميزة واحدة من الأساليب المقدمة هنا هو الحصول على الخلايا الحية المفيدة للتحقيقات الفسيولوجية. إلى جانب استخدامها في تجارب المشبك التصحيح لدراسة قنوات الجهد بوابات (كما هو موضح هنا) ويمكن تمديد استخدام هذه الخلايا لدراسة الرنين الخلية 9،10، ورصد إطلاق الناقل العصبي من خلال جعل القياسات السعة 11،12 والتحقيق تعديل العمليات العصبية الناجمة عن تفعيل قنوات بوابات يجند 13 وكذلك الاستفادة من ثروة من المعلومات التي يمكن استخلاصها من استخدام المسوخ التي تؤثر على كل من السمع والتوازن 14.

<table border="1" style=";text-align:right;direction:rtl"><tbody><tr><td> حل اسم </td><td> وصفة </td></tr><tr><td> (أ) NZR (عادي اسماك الزرد رينغر) (مم) </td><td> 116 كلوريد الصوديوم، 2 بوكل، 2 CaCl 2، 3 الجلوكوز، 5 نا +-HEPES، ودرجة الحموضة 7.35. </td></tr><tr><td> (ب) NZR + Tricaine </td><td> NZR + 0.02٪ 3-أمينوبنزويك حمض السلفونات اثيل استر الميثان (سيغما A5040). </td></tr><tr><td> (ج) BSA + NZR </td><td> NZR + 0.4٪ الأبقار مصل الزلال (سيغما A2153). </td></tr><tr><td> (د) لوكاس (منخفضة الكالسيوم الحل + 2) (مم) </td><td> 100 كلوريد الصوديوم، 2 بوكل، 0.05 CaCl 2، 0،05 MgCl 2، 3 الجلوكوز، 30 نا +-HEPES، ودرجة الحموضة 7.35. </td></tr><tr><td> (ه) لوكاس + غراء </td><td> لوكاس + 0.05٪ L-السيستين (سيغما C1276) + غراء 0.2٪ (سيغما P3375). </td></tr><tr><td> (و) K +-الداخلية حل (مم) </td><td> 52 K 2 SO 4،38 بوكل، 1 K +-EGTA، 5 K +-HEPES، ودرجة الحموضة 7.3. </td></tr></tbody></table> الجدول 1. حلول.

patch clamp recordings in inner ear hair cells isolated from zebrafish

وقد وصفت التحليلات المشبك التصحيح من القنوات الجهد مسور في الخلايا الحسية الشعر معزولة عن مجموعة متنوعة من الأنواع سابقا 1-4 لكن هذا الفيديو يمثل أول تطبيق لتلك التقنيات إلى خلايا الشعر من الزرد. نحن هنا يبرهن على وجود طريقة لعزل صحي، وخلايا الشعر سليمة من جميع الأجهزة في نهاية الأذن الداخلية: كيس، والحوقلة، والقنوات الهلالية utricle. علاوة على ذلك، علينا أن نبرهن على التنوع في حجم خلية الشعر والصرف وإعطاء مثال لهذا النوع من التسجيلات المشبك التصحيح التي يمكن الحصول عليها. ميزة استخدام هذا النظام النموذجي الزرد على الآخرين نابع من توافر المسوخ الزرد أن تؤثر على كل من السمع والتوازن. في تركيبة مع استخدام خطوط المعدلة وراثيا وغيرها من التقنيات التي تستخدم التحليل الجيني والتلاعب، وعزل الخلايا الكهربية وطرق عرض هنا ينبغي تسهيل مزيد من التبصر في خلايا الشعر أدوار عيكمن في الوساطة هذه الطرائق الحسية.

Watch this Scientific Journal Video about Patch Clamp Recordings in Inner Ear Hair Cells Isolated from Zebrafish at JoVE.com

Patch Clamp Recordings in Inner Ear Hair Cells Isolated from Zebrafish

والغرض من هذا الفيديو هو إظهار إجراءات الحصول على صحي، وخلايا الشعر سليمة من الأجهزة الأذن الداخلية من الزرد الكبار ومن ثم استخدامها للدراسات المشبك التصحيح تهدف إلى تحديد خواص الفيزيائية الحيوية من القنوات الجهد بوابات بهم.

تسجيلات المشبك التصحيح في الأذن الداخلية خلايا الشعر المعزولة من اسماك الزرد

Patch  clamp analyses of the voltage-gated channels in sensory hair cells isolated  from a variety of species have been described previously1-4 but this  ...

patch-clamp-recordings-in-inner-ear-hair-cells-isolated-from-zebrafish

Research

JoVE Journal

Neuroscience

16.6K Views.  Pepperdine University. والغرض من هذا الفيديو هو إظهار إجراءات الحصول على صحي، وخلايا الشعر سليمة من الأجهزة الأذن الداخلية من الزرد الكبار ومن ثم استخدامها للدراسات المشبك التصحيح تهدف إلى تحديد خواص الفيزيائية الحيوية من القنوات الجهد بوابات بهم.

Video: Patch Clamp Recordings in Inner Ear Hair Cells Isolated from Zebrafish

Patch Clamp Recordings from Mouse Retinal Neurons in a Dark-adapted Slice Preparation

Our visual experience is initiated when the visual pigment in our retinal photoreceptors absorbs photons of light energy and initiates a cascade of intracellular events that lead to closure of cyclic-nucleotide-gated channels in the cell membrane. The resulting change in membrane potential leads in turn to reductions in the amount of neurotransmitter release from both rod and cone synaptic terminals. To measure how the light-evoked change in photoreceptor membrane potential leads to downstream activity in the retina, scientists have made electrophysiological recordings from retinal slice preparations for decades1,2. In the past these slices have been cut manually with a razor blade on retinal tissue that is attached to filter paper; in recent years another method of slicing has been developed whereby retinal tissue is embedded in low gelling temperature agar and sliced in cool solution with a vibrating microtome3,4. This preparation produces retinal slices with less surface damage and very robust light-evoked responses. Here we document how this procedure can be done under infrared light to avoid bleaching the visual pigment.

Here we describe a procedure for generating dark-adapted slices of the mouse retina for electrophysiological recordings.

تسجيلات المشبك التصحيح من الخلايا العصبية في الشبكية ماوس إعداد غامق تكييفها شريحة

Our visual experience is initiated when the visual pigment in our retinal photoreceptors absorbs photons of light energy and initiates a cascade of ...

Paired Patch Clamp Recordings from Motor-neuron and Target Skeletal Muscle in Zebrafish

Larval zebrafish represent the first vertebrate model system to allow simultaneous patch clamp recording from a spinal motor-neuron and target muscle. This is a direct consequence of the accessibility to both cell types and ability to visually distinguish the single segmental CaP motor-neuron on the basis of morphology and location. This video demonstrates the microscopic methods used to identify a CaP motor-neuron and target muscle cells as well as the methodologies for recording from each cell type. Identification of the CaP motor-neuron type is confirmed by either dye filling or by the biophysical features such as action potential waveform and cell input resistance. Motor-neuron recordings routinely last for one hour permitting long-term recordings from multiple different target muscle cells. Control over the motor-neuron firing pattern enables measurements of the frequency-dependence of synaptic transmission at the neuromuscular junction. Owing to a large quantal size and the low noise provided by whole cell voltage clamp, all of the unitary events can be resolved in muscle. This feature permits study of basic synaptic properties such as release properties, vesicle recycling, as well as synaptic depression and facilitation. The advantages offered by this in vivo preparation eclipse previous neuromuscular model systems studied wherein the motor-neurons are usually stimulated by extracellular electrodes and the muscles are too large for whole cell patch clamp. The zebrafish preparation is amenable to combining electrophysiological analysis with a wide range of approaches including transgenic lines, morpholino knockdown, pharmacological intervention and in vivo imaging. These approaches, coupled with the growing number of neuromuscular disease models provided by mutant lines of zebrafish, open the door for new understanding of human neuromuscular disorders.

Larval zebrafish represent the first vertebrate model system to allow simultaneous patch clamp recording from a spinal motor-neuron and target skeletal muscle. This video demonstrates the microscopic methods used to identify a segmental CaP motor-neuron and target muscle cells as well as the methodologies for recording from each cell type.

المقترنة تسجيلات المشبك من تصحيح للسيارات ، والخلايا العصبية في العضلات الهيكلية الهدف اسماك الزرد

Larval zebrafish represent the first vertebrate model system to allow simultaneous patch clamp recording from a spinal motor-neuron and target muscle.  ...

Postsynaptic Recordings at Afferent Dendrites Contacting Cochlear Inner Hair Cells: Monitoring Multivesicular Release at a Ribbon Synapse

The afferent synapse between the inner hair cell (IHC) and the auditory nerve fiber provides an electrophysiologically accessible site for recording the postsynaptic activity of a single ribbon synapse 1-4. Ribbon synapses of sensory cells release neurotransmitter continuously, the rate of which is modulated in response to graded changes in IHC membrane potential 5. Ribbon synapses have been shown to operate by multivesicular release, where multiple vesicles can be released simultaneously to evoke excitatory postsynaptic currents (EPSCs) of varying amplitudes 1, 4, 6-11. Neither the role of the presynaptic ribbon, nor the mechanism underlying multivesicular release is currently well understood.
The IHC is innervated by 10-20 auditory nerve fibers, and every fiber contacts the IHC with a unmyelinated single ending to form a single ribbon synapse. The small size of the afferent boutons contacting IHCs (approximately 1 &mu;m in diameter) enables recordings with exceptional temporal resolution to be made. Furthermore, the technique can be adapted to record from both pre- and postsynaptic cells simultaneously, allowing the transfer function at the synapse to be studied directly 2. This method therefore provides a means by which fundamental aspects of neurotransmission can be studied, from multivesicular release to the elusive function of the ribbon in sensory cells.

Whole-cell patch-clamp recordings from auditory nerve fiber dendrites at the inner hair cell ribbon synapse in the mammalian cochlea.

بعد المشبكي التسجيلات في وارد الاتصال الانشعابيات القوقعة خلايا الشعر الداخلية : رصد النسخة عديد الحويصلات في الشريط المشبك

The afferent synapse between the inner hair cell (IHC) and the auditory nerve fiber provides an electrophysiologically accessible site for recording the ...

Isolating LacZ-expressing Cells from Mouse Inner Ear Tissues using Flow Cytometry

Isolation of specific cell types allows one to analyze rare cell populations such as stem/progenitor cells. Such an approach to studying inner ear tissues presents a unique challenge because of the paucity of cells of interest and few transgenic reporter mouse models. Here, we describe a protocol using fluorescence-conjugated probes to selectively label LacZ-positive cells from the neonatal cochleae.
The most common underlying pathology of sensorineural hearing loss is the irreversible damage and loss of cochlear sensory hair cells, which are required to transduce sound waves to neural impulses. Recent evidence suggests that the murine auditory and vestibular organs harbor stem/progenitor cells that may have regenerative potential1,2. These findings warrant further investigation, including identifying specific cell types with stem/progenitor cell characteristics. The Wnt signaling pathway has been demonstrated to play a critical role in maintaining stem/progenitor cell populations in several organ systems3-7. We have recently identified Wnt-responsive Axin2-expressing cells in the neonatal cochlea, but their function is largely unknown8.
To better understand the behavior of these Wnt-responsive cells in vitro, we have developed a method of isolating Axin2-expressing cells from cochleae of Axin2-LacZ reporter mice9. Using flow cytometry to isolate Axin2-LacZ positive cells from the neonatal cochleae, we could in turn execute a variety of experiments on live cells to interrogate their behavior as stem/progenitor cells. Here, we describe in detail the steps for the microdissection of neonatal cochlea, dissociation of these tissues, labeling of the LacZ-positive cells using a fluorogenic substrate, and cell sorting. Techniques for dissociating cochleae into single cells and isolating cochlear cells via flow cytometry have been described2,10-12. We have made modifications to these techniques to establish a novel protocol to isolate LacZ-expressing cells from the neonatal cochlea.

Flow cytometry is a powerful tool allowing for the isolation and study of specific cell populations. This protocol describes steps for isolating LacZ-expressing cells from cochlear tissues from neonatal transgenic mice. Dissociated cochlear cells were labeled using fluorescent-conjugated substrates of &#946;-galactosidase prior to separation via flow cytometry.

عزل LacZ - معربا عن خلايا من أنسجة الأذن الداخلية باستخدام الماوس التدفق الخلوي

Isolation of specific cell types allows one to analyze rare cell populations such as stem/progenitor cells. Such an approach to studying inner ear tissues ...

Gene Transfer to the Developing Mouse Inner Ear by In Vivo Electroporation

The mammalian inner ear has 6 distinct sensory epithelia: 3 cristae in the ampullae of the semicircular canals; maculae in the utricle and saccule; and the organ of Corti in the coiled cochlea. The cristae and maculae contain vestibular hair cells that transduce mechanical stimuli to subserve the special sense of balance, while auditory hair cells in the organ of Corti are the primary transducers for hearing 1. Cell fate specification in these sensory epithelia and morphogenesis of the semicircular canals and cochlea take place during the second week of gestation in the mouse and are largely completed before birth 2,3. Developmental studies of the mouse inner ear are routinely conducted by harvesting transgenic embryos at different embryonic or postnatal stages to gain insight into the molecular basis of cellular and/or morphological phenotypes 4,5. We hypothesize that gene transfer to the developing mouse inner ear in utero in the context of gain- and loss-of-function studies represents a complimentary approach to traditional mouse transgenesis for the interrogation of the genetic mechanisms underlying mammalian inner ear development6.
The experimental paradigm to conduct gene misexpression studies in the developing mouse inner ear demonstrated here resolves into three general steps: 1) ventral laparotomy; 2) transuterine microinjection; and 3) in vivo electroporation. Ventral laparotomy is a mouse survival surgical technique that permits externalization of the uterus to gain experimental access to the implanted embryos7. Transuterine microinjection is the use of beveled, glass capillary micropipettes to introduce expression plasmid into the lumen of the otic vesicle or otocyst. In vivo electroporation is the application of square wave, direct current pulses to drive expression plasmid into progenitor cells8-10. 
We previously described this electroporation-based gene transfer technique and included detailed notes on each step of the protocol11. Mouse experimental embryological techniques can be difficult to learn from prose and still images alone. In the present work, we demonstrate the 3 steps in the gene transfer procedure. Most critically, we deploy digital video microscopy to show precisely how to: 1) identify embryo orientation in utero; 2) reorient embryos for targeting injections to the otocyst; 3) microinject DNA mixed with tracer dye solution into the otocyst at embryonic days 11.5 and 12.5; 4) electroporate the injected otocyst; and 5) label electroporated embryos for postnatal selection at birth. We provide representative examples of successfully transfected inner ears; a pictorial guide to the most common causes of otocyst mistargeting; discuss how to avoid common methodological errors; and present guidelines for writing an in utero gene transfer animal care protocol.

Gene Transfer to the Developing Mouse Inner Ear by In Vivo Electroporation

The mouse inner ear is a placode-derived sensory organ whose developmental program is elaborated during gestation. We define an in utero gene transfer technique consisting of three steps: mouse ventral laparotomy, transuterine microinjection, and in vivo electroporation. We use digital video microscopy to demonstrate the critical experimental embryological techniques.

نقل الجينات إلى الأذن الداخلية عن طريق تطوير ماوس<em&gt; في الجسم الحي</em&gt; Electroporation

The mammalian inner ear has 6 distinct sensory epithelia: 3 cristae in the ampullae of the semicircular canals; maculae in the utricle and saccule; and ...

Patch Clamp Recordings from Embryonic Zebrafish Mauthner Cells

Mauthner cells (M-cells) are large reticulospinal neurons located in the hindbrain of teleost fish. They are key neurons involved in a characteristic behavior known as the C-start or escape response that occurs when the organism perceives a threat. The M-cell has been extensively studied in adult goldfish where it has been shown to receive a wide range of excitatory, inhibitory and neuromodulatory signals1. We have been examining M-cell activity in embryonic zebrafish in order to study aspects of synaptic development in a vertebrate preparation. In the late 1990s Ali and colleagues developed a preparation for patch clamp recording from M-cells in zebrafish embryos, in which the CNS was largely intact2,3,4. The objective at that time was to record synaptic activity from hindbrain neurons, spinal cord neurons and trunk skeletal muscle while maintaining functional synaptic connections within an intact brain-spinal cord preparation. This preparation is still used in our laboratory today. To examine the mechanisms underlying developmental synaptic plasticity, we record excitatory (AMPA and NMDA-mediated)5,6 and inhibitory (GABA and glycine) synaptic currents from developing M-cells. Importantly, this unique preparation allows us to return to the same cell (M-cell) from preparation to preparation to carefully examine synaptic plasticity and neuro-development in an embryonic organism. The benefits provided by this preparation include 1) intact, functional synaptic connections onto the M-cell, 2) relatively inexpensive preparations, 3) a large supply of readily available embryos 4) the ability to return to the same cell type (i.e. M-cell) in every preparation, so that synaptic development at the level of an individual cell can be examined from fish to fish, and 5) imaging of whole preparations due to the transparent nature of the embryos.

We have developed an intact brain-spinal cord preparation to record and monitor electrical activity via patch clamp recording from the Mauthner neurons and other reticulospinal cells in zebrafish embryos. Thus, we are able to record excitatory and inhibitory synaptic currents, voltage-gated channel activity and action potentials from key neurons in a developing embryo.

تسجيلات المشبك التصحيح من الخلايا الجنينية الزرد ماوتنر

Mauthner cells (M-cells) are large  reticulospinal neurons located in the hindbrain of teleost fish. They are key  neurons involved in a characteristic ...

Whole-cell Patch-clamp Recordings from Morphologically- and Neurochemically-identified Hippocampal Interneurons

GABAergic inhibitory interneurons play a central role within neuronal circuits of the brain. Interneurons comprise a small subset of the neuronal population (10-20%), but show a high level of physiological, morphological, and neurochemical heterogeneity, reflecting their diverse functions. Therefore, investigation of interneurons provides important insights into the organization principles and function of neuronal circuits. This, however, requires an integrated physiological and neuroanatomical approach for the selection and identification of individual interneuron types. Whole-cell patch-clamp recording from acute brain slices of transgenic animals, expressing fluorescent proteins under the promoters of interneuron-specific markers, provides an efficient method to target and electrophysiologically characterize intrinsic and synaptic properties of specific interneuron types. Combined with intracellular dye labeling, this approach can be extended with post-hoc morphological and immunocytochemical analysis, enabling systematic identification of recorded neurons. These methods can be tailored to suit a broad range of scientific questions regarding functional properties of diverse types of cortical neurons.

Cortical networks are controlled by a small, but diverse set of inhibitory interneurons. Functional investigation of interneurons therefore requires targeted recording and rigorous identification. Described here is a combined approach involving whole-cell recordings from single or synaptically-coupled pairs of neurons with intracellular labeling, post-hoc morphological and immunocytochemical analysis.

خلية كاملة تسجيلات التصحيح، المشبك من Morphologically- وحددت Neurochemically-الحصين Interneurons

GABAergic inhibitory interneurons play a central role within neuronal circuits of the brain. Interneurons comprise a small subset of the neuronal ...

Electrophysiological and Morphological Characterization of Neuronal Microcircuits in Acute Brain Slices Using Paired Patch-Clamp Recordings

The combination of patch clamp recordings from two (or more) synaptically coupled neurons (paired recordings) in acute brain slice preparations with simultaneous intracellular biocytin filling allows a correlated analysis of their structural and functional properties. With this method it is possible to identify and characterize both pre- and postsynaptic neurons by their morphology and electrophysiological response pattern. Paired recordings allow studying the connectivity patterns between these neurons as well as the properties of both chemical and electrical synaptic transmission. Here, we give a step-by-step description of the procedures required to obtain reliable paired recordings together with an optimal recovery of the neuron morphology. We will describe how pairs of neurons connected via chemical synapses or gap junctions are identified in brain slice preparations. We will outline how neurons are reconstructed to obtain their 3D morphology of the dendritic and axonal domain and how synaptic contacts are identified and localized. We will also discuss the caveats and limitations of the paired recording technique, in particular those associated with dendritic and axonal truncations during the preparation of brain slices because these strongly affect connectivity estimates. However, because of the versatility of the paired recording approach it will remain a valuable tool in characterizing different aspects of synaptic transmission at identified neuronal microcircuits in the brain.

Patch-clamp recordings and simultaneous intracellular biocytin filling of synaptically coupled neurons in acute brain slices allow a correlated analysis of their structural and functional properties. The aim of this protocol is to describe the essential technical steps of electrophysiological recording from neuronal microcircuits and their subsequent morphological analysis.

الكهربية والمورفولوجية توصيف العصبية الحادة رقائق في الدماغ عن طريق شرائح الموثوقة التصحيح، المشبك التسجيلات

The combination of patch clamp recordings from two (or more) synaptically coupled neurons (paired recordings) in acute brain slice preparations with ...

Whole-cell Patch-clamp Recordings in Brain Slices

Whole-cell patch-clamp recording is an electrophysiological technique that allows the study of the&#160;electrical properties of a substantial part of the neuron. In this configuration, the micropipette is in tight contact with the cell membrane, which prevents current leakage and thereby provides more accurate ionic current measurements than the previously used intracellular sharp electrode recording method. Classically, whole-cell recording can be performed on neurons in various types of preparations, including cell culture models, dissociated neurons, neurons in brain slices, and in intact anesthetized or awake animals. In summary, this technique has immensely contributed to the understanding of passive and active biophysical properties of excitable cells. A major advantage of this technique is that it provides information on how specific manipulations (e.g., pharmacological, experimenter-induced plasticity) may alter specific neuronal functions or channels in real-time. Additionally, significant opening of the plasma membrane allows the internal pipette solution to freely diffuse into the cytoplasm, providing means for introducing drugs, e.g., agonists or antagonists of specific intracellular proteins, and manipulating these targets without altering their functions in neighboring cells. This article will focus on whole-cell recording performed on neurons in brain slices,&#160;a preparation that has the advantage of recording neurons in relatively well preserved brain circuits, i.e., in a physiologically relevant context. In particular,&#160;when combined with appropriate pharmacology, this technique is a powerful tool allowing identification of specific neuroadaptations that occurred following any type of experiences, such as learning, exposure to drugs of abuse, and stress. In summary, whole-cell patch-clamp recordings in brain slices provide means to measure in ex vivo preparation long-lasting changes in neuronal functions that have developed in intact awake animals.

This protocol describes basic procedural steps for performing whole-cell patch-clamp recordings. This technique allows the study of&#160;the electrical behavior of neurons, and when performed in brain slices, allows the assessment of various neuronal functions from neurons that are still integrated in relatively well preserved brain circuits.

تسجيلات خلية كاملة التصحيح، المشبك في الدماغ شرائح

Whole-cell patch-clamp recording is an electrophysiological technique that allows the study of the&#160;electrical properties of a substantial part of the ...

Subcellular Patch-clamp Recordings from the Somatodendritic Domain of Nigral Dopamine Neurons

Dendrites of dopaminergic neurons receive and convey synaptic input, support action potential back-propagation and neurotransmitter release. Understanding these fundamental functions will shed light on the information transfer in these neurons. Dendritic patch-clamp recordings provide the possibility to directly examine the electrical properties of dendrites and underlying voltage-gated ion channels. However, these fine structures are not easily accessible to patch pipettes because of their small diameter. This report describes a step-by-step procedure to collect stable and reliable recordings from the dendrites of dopaminergic neurons in acute slices. Electrophysiological measurements are combined with post hoc recovery of cell morphology. Successful experiments rely on improved preparation of slices, solutions and pipettes, adequate adjustment of the optics and stability of the pipette in contact with the recorded structure. Standard principles of somatic patch-clamp recording are applied to dendrites but with a gentler approach of the pipette. These versatile techniques can be implemented to address various questions concerning the excitable properties of dendrites.

Subcellular patch-clamp recordings offer the possibility to investigate the functional properties of dendrites. However these fine structures are not easily accessible due to their small diameter. The protocol described here aims to facilitate the collection of stable and reliable recordings from the dendrites of dopamine neurons in slices in vitro.

التحت خلوية تسجيلات التصحيح، المشبك من المجال Somatodendritic من سودائي الدوبامين العصبية

Dendrites of dopaminergic neurons receive and convey synaptic input, support action potential back-propagation and neurotransmitter release. Understanding ...