<meta charset="utf8"></head><body>Registros de multielectrodos de silicio en ángulo para estructuras profundas del tronco encefálico en ratones

<ol>
	<li>Wu, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Monolithically+integrated+&#181;LEDs+on+silicon+neural+probes+for+high-resolution+optogenetic+studies+in+behaving+animals.">Monolithically integrated &#181;LEDs on silicon neural probes for high-resolution optogenetic studies in behaving animals.</a> Neuron. 88 (6), 1136-1148 (2015).</li><li>Hong, G., Lieber, C. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Novel+electrode+technologies+for+neural+recordings.">Novel electrode technologies for neural recordings.</a> Nat Rev Neurosci. 20 (6), 330-345 (2019).</li><li>Li, N., Daie, K., Svoboda, K., Druckmann, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Robust+neuronal+dynamics+in+premotor+cortex+during+motor+planning.">Robust neuronal dynamics in premotor cortex during motor planning.</a> Nature. 532 (7600), 459-464 (2016).</li><li>Kipke, D. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Advanced+neurotechnologies+for+chronic+neural+interfaces:+New+horizons+and+clinical+opportunities.">Advanced neurotechnologies for chronic neural interfaces: New horizons and clinical opportunities.</a> J Neurosci. 28 (46), 11830-11838 (2008).</li><li>Steinmetz, N. A., Koch, C., Harris, K. D., Carandini, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Challenges+and+opportunities+for+large-scale+electrophysiology+with+Neuropixels+probes.">Challenges and opportunities for large-scale electrophysiology with Neuropixels probes.</a> Curr Opinion Neurobiol. 50, 92-100 (2018).</li><li>Nunez-Elizalde, A. O., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neural+correlates+of+blood+flow+measured+by+ultrasound.">Neural correlates of blood flow measured by ultrasound.</a> Neuron. 110 (10), 1631-1640.e4 (2022).</li><li>Yang, L., Lee, K., Villagracia, J., Masmanidis, S. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Open+source+silicon+microprobes+for+high+throughput+neural+recording.">Open source silicon microprobes for high throughput neural recording.</a> J Neural Eng. 17 (1), 016036 (2020).</li><li>Jun, J. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fully+integrated+silicon+probes+for+high-density+recording+of+neural+activity.">Fully integrated silicon probes for high-density recording of neural activity.</a> Nature. 551 (7679), 232-236 (2017).</li><li>Augustinaite, S., Kuhn, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chronic+cranial+window+for+imaging+cortical+activity+in+head-fixed+mice.">Chronic cranial window for imaging cortical activity in head-fixed mice.</a> STAR Protoc. 1 (3), 100194 (2020).</li><li>Dias, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transection+of+the+superior+sagittal+sinus+enables+bilateral+access+to+the+rodent+midline+brain+structures.">Transection of the superior sagittal sinus enables bilateral access to the rodent midline brain structures.</a> eNeuro. 8 (4), (2021).</li><li>Gao, Z. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tac1-expressing+neurons+in+the+periaqueductal+gray+facilitate+the+itch-scratching+cycle+via+descending+regulation.">Tac1-expressing neurons in the periaqueductal gray facilitate the itch-scratching cycle via descending regulation.</a> Neuron. 101 (1), 45-59.e9 (2019).</li><li>Atluri, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Anatomical+substrates+of+rapid+eye+movement+sleep+rebound+in+a+rodent+model+of+post-sevoflurane+sleep+disruption.">Anatomical substrates of rapid eye movement sleep rebound in a rodent model of post-sevoflurane sleep disruption.</a> Anesthesiology. 140 (4), 729-741 (2023).</li><li>Weber, F., Dan, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Circuit-based+interrogation+of+sleep+control.">Circuit-based interrogation of sleep control.</a> Nature. 538 (7623), 51-59 (2016).</li><li>Frontera, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bidirectional+control+of+fear+memories+by+cerebellar+neurons+projecting+to+the+ventrolateral+periaqueductal+grey.">Bidirectional control of fear memories by cerebellar neurons projecting to the ventrolateral periaqueductal grey.</a> Nat Commun. 11 (1234567890), (2020).</li><li>Weber, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regulation+of+REM+and+Non-REM+sleep+by+periaqueductal+GABAergic+neurons.">Regulation of REM and Non-REM sleep by periaqueductal GABAergic neurons.</a> Nat Commun. 9 (1), 354 (2018).</li><li>Buzs&#225;ki, G., Anastassiou, C. A., Koch, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+origin+of+extracellular+fields+and+currents--EEG,+ECoG,+LFP+and+spikes.">The origin of extracellular fields and currents--EEG, ECoG, LFP and spikes.</a> Nat Rev Neurosci. 13 (6), 407-420 (2012).</li><li>Franklin, K. B. J., Paxinos, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The mouse brain in stereotaxic coordinates. , (2008).</li><li>. Pythagorean theorem Available from: <a target="_blank" href="https://en.wikipedia.org/w/index.php?title=Pythagorean_theorem&amp;oldid=1222259845">https://en.wikipedia.org/w/index.php?title=Pythagorean_theorem&amp;oldid=1222259845</a> (2024)</li><li>. The Anatomy of the Laboratory Mouse Available from: <a target="_blank" href="https://www.informatics.jax.org/cookbook/chapters/skeleton.shtml">https://www.informatics.jax.org/cookbook/chapters/skeleton.shtml</a> (2024)</li><li>Cecyn, M. N., Abrahao, K. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Where+do+you+measure+the+Bregma+for+rodent+stereotaxic+surgery.">Where do you measure the Bregma for rodent stereotaxic surgery.</a> IBRO Neurosci Rep. 15, 143-148 (2023).</li><li>Fi&#225;th, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Slow+insertion+of+silicon+probes+improves+the+quality+of+acute+neuronal+recordings.">Slow insertion of silicon probes improves the quality of acute neuronal recordings.</a> Sci Rep. 9, 111 (2019).</li><li>Wu, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transcardiac+perfusion+of+the+mouse+for+brain+tissue+dissection+and+fixation.">Transcardiac perfusion of the mouse for brain tissue dissection and fixation.</a> Bio-protocol. 11 (5), e3988 (2021).</li><li>Peters, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> petersaj/AP_histology. , (2024).</li><li>Pachitariu, M., Sridhar, S., Stringer, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Solving the spike sorting problem with Kilosort. , (2023).</li><li>Akam, T., Walton, M. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=pyPhotometry:+Open+source+Python+based+hardware+and+software+for+fiber+photometry+data+acquisition.">pyPhotometry: Open source Python based hardware and software for fiber photometry data acquisition.</a> Sci Rep. 9 (1), 3521 (2019).</li><li>Leiras, R., Cregg, J. M., Kiehn, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Brainstem+circuits+for+locomotion.">Brainstem circuits for locomotion.</a> Ann Rev Neurosci. 45 (2022), 63-85 (2022).</li><li>Benarroch, E. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Brainstem+integration+of+arousal,+sleep,+cardiovascular,+and+respiratory+control.">Brainstem integration of arousal, sleep, cardiovascular, and respiratory control.</a> Neurology. 91 (21), 958-966 (2018).</li><li>Guyenet, P. G., Bayliss, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neural+control+of+breathing+and+CO2+homeostasis.">Neural control of breathing and CO2 homeostasis.</a> Neuron. 87 (5), 946-961 (2015).</li><li>Potter, K. A., Buck, A. C., Self, W. K., Capadona, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stab+injury+and+device+implantation+within+the+brain+results+in+inversely+multiphasic+neuroinflammatory+and+neurodegenerative+responses.">Stab injury and device implantation within the brain results in inversely multiphasic neuroinflammatory and neurodegenerative responses.</a> J Neural Eng. 9 (4), 046020 (2012).</li></ol>

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>1024 channel RHD Recording Controller</td>
			<td>Intan Technologies, Los Angeles, California, USA</td>
			<td>C3008</td>
			<td>Silicon probe recording; recording hardware and software</td>
			<td></td>
		</tr>
		<tr>
			<td>24 mm x 50 mm No. 1.5 VWR coverslip</td>
			<td>VWR, Radnor, Pennsylvania, USA</td>
			<td>48393-081</td>
			<td>Histology</td>
			<td></td>
		</tr>
		<tr>
			<td>4% PFA in PBS</td>
			<td>ThermoFisher Scientific, Waltham, Massachusetts, USA</td>
			<td>J61899.AK</td>
			<td>Histology; perfusion solution</td>
			<td></td>
		</tr>
		<tr>
			<td>C&#38;B metabond</td>
			<td>Patterson Dental, Richmond, Virginia, USA</td>
			<td>powder: 5533559, quick base: 5533492, catalyst: 55335007</td>
			<td>Headplate &#38;Headset Implantation</td>
			<td></td>
		</tr>
		<tr>
			<td>C57/6J mice 4-6 weeks, males</td>
			<td>The Jackson Laboratory, Bar Harbor, Maine, USA</td>
			<td>000664</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Capnomac Ultima</td>
			<td>Datex, Helsinki, Finland&#160;</td>
			<td>ULT-SVi-27-07</td>
			<td>Gas Analyzer; discontinued; alternative gas analyzer can be purchased from Bionet America&#160;</td>
			<td></td>
		</tr>
		<tr>
			<td>CM-DiI</td>
			<td>ThermoFisher Scientific, Waltham, Massachusetts, USA</td>
			<td>V22888</td>
			<td>Red fluorescent dye for coating of the silicon probe</td>
			<td></td>
		</tr>
		<tr>
			<td>Connector Header</td>
			<td>DigiKey, Thief River Falls, Minnesota, USA</td>
			<td>1212-1788-ND</td>
			<td>ECoG Headset</td>
			<td></td>
		</tr>
		<tr>
			<td>DAPI Fluoromount-G</td>
			<td>SouthernBiotech, Birmingham, Alabama, USA</td>
			<td>0100-20</td>
			<td>Histology</td>
			<td></td>
		</tr>
		<tr>
			<td>iBOND Universal</td>
			<td>Patterson Dental, Richmond, Virginia, USA</td>
			<td>044-1113</td>
			<td>Headplate &#38;Headset Implantation; for&#160; securing stainless steel wires to the skull</td>
			<td></td>
		</tr>
		<tr>
			<td>Low toxicity silicon adhesive</td>
			<td>World Precision Instruments, Sarasota, Florida, USA</td>
			<td>KWIK-SIL</td>
			<td>Headplate</td>
			<td></td>
		</tr>
		<tr>
			<td>Micro-Manipulator System</td>
			<td>New Scale Technologies, Victor, New York, USA</td>
			<td>Multi-Probe Manipulator: XYZ Stage Assembly: 06464-0000, MPM System Kit: 06267-3-0001, MPM-Platform-360, MPM ring for MPM Manual Arms, MPM_Ring-72 DEG: 06262-3-0000</td>
			<td>Silicon probe recording; inserting the probe into the brain</td>
			<td></td>
		</tr>
		<tr>
			<td>Microprobes</td>
			<td>UCLA, Los Angeles, California, USA</td>
			<td>256 ANS, 64M</td>
			<td>Discontinued; alternative silicon probes can be purchased from Neuropixels</td>
			<td></td>
		</tr>
		<tr>
			<td>Mineral Oil</td>
			<td>Sigma Aldrich, Saint Luis, Missouri, USA</td>
			<td>M8410-100ML</td>
			<td>Silicon probe recording; preventing the tissue from drying during the recording</td>
			<td></td>
		</tr>
		<tr>
			<td>Normal saline</td>
			<td>ThermoFisher Scientific, Waltham, Massachusetts, USA</td>
			<td>Z1376</td>
			<td>Headplate &#38;Headset Implantation; preventing the brain from drying during the surgery</td>
			<td></td>
		</tr>
		<tr>
			<td>PFA-Coated Stainless Steel Wire-Diameter 0.008 in. coated with striped ends</td>
			<td>A-M systems, Sequim, Washington, USA</td>
			<td>791400</td>
			<td>ECoG Headset &#38; reference electrode for ECoG&#160;</td>
			<td></td>
		</tr>
		<tr>
			<td>Platinum wire 24AWG&#160;</td>
			<td>World Precision Instruments, Sarasota, Florida, USA</td>
			<td>PTP201</td>
			<td>Reference electrode for the silicon probe recording&#160;</td>
			<td></td>
		</tr>
		<tr>
			<td>Shandon Colorfrost Plus microscope slides</td>
			<td>ThermoFisher Scientific, Waltham, Massachusetts, USA</td>
			<td>99-910-01</td>
			<td>Histology</td>
			<td></td>
		</tr>
		<tr>
			<td>Stainless steel Headplate</td>
			<td>Star Rapid, China</td>
			<td>custom made part</td>
			<td>Headplate &#38;Headset Implantation; design available upon request</td>
			<td></td>
		</tr>
		<tr>
			<td>Stereotaxic apparatus</td>
			<td>KOPF, Tujunga, California, USA</td>
			<td>Model 940 Small Animal Stereotaxic Instrument with Digital Display Console</td>
			<td>Headplate &#38;Headset Implantation</td>
			<td></td>
		</tr>
	</tbody>
</table>

acute single-unit multi-electrode recordings from the brainstem of head-fixed mice

Silicon multielectrode-based recordings are becoming increasingly popular to measure neuronal activity across many brain regions with single action potential resolution1,2,3,4. Over the last decade, high-density recording technology has grown considerably. Current silicon-based recording electrodes can accommodate high channel counts, optical fibers, and electrocorticography (ECoG) recording devices5,6. Moreover, chronic implantation of these electrodes allows for long-term recordings7,8.
Despite recent technological advancements, targeting deep caudal structures like the brainstem with multi-channel probes remains challenging. When targeting brainstem structures such as the ventrolateral periacqueductal gray (vlPAG), one significant obstacle is identifying a probe trajectory that avoids major blood vessels, e.g., the superior sagittal venous sinus and the transverse venous sinus. Injury to these large veins can cause extensive bleeding, damage to the underlying brain tissue, and even death9,10. We propose targeting brainstem structures from anterior coordinates at an angle, allowing the recording probe to penetrate the brain below such high-risk vascular structures (see Figure 1). This angled approach, compared to a vertical one, maximizes the number of brain regions accessible for recording. Additionally, in experimental circumstances wherein ECoG recordings are desired, the angled anterior approach affords more skull surface available for ECoG headset implantation, as the craniotomy window for probe insertion is positioned more anteriorly10,11.
Identifying the specific cell groups and circuits responsible for anesthesia-induced REM sleep changes remains a major goal of anesthesia research. Thus, the objective here was to reproducibly and reliably access the vlPAG - a brainstem region associated with REM sleep - to obtain single unit, multi-electrode recordings in head-fixed mice before and during sevoflurane anesthesia12,13. Previous studies have used electrophysiological local field potential (LFP) measurements of the vlPAG in awake mice to identify neural state changes associated with anesthesia14,15. However, LFP measurements are primarily sensitive to synaptic activity, not action potentials, within the recorded area16. Consequently, there remains a limited understanding of how anesthetics directly affect the neural activity patterns produced by vlPAG neurons. Here, a method is described to obtain high-density single-neuron recordings from the brainstem of head-fixed mice. This method can also be adapted to record single-neuron activity from various other deep and posterior brainstem structures.

<meta charset="utf8"></head><body>Autor destacado: Investigación de las vías del sueño inducidas por la anestesia y la excitabilidad neuronal en ratones

Registros agudos de electrodos múltiples de una sola unidad del tronco encefálico de ratones con cabeza fija

Our laboratory investigates the effects of commonly used anesthetics on sleep-related neurons and their communication pathways. We aim to better understand how anesthetics impact endogenous sleep pathways and affect perioperative sleep and cognition. Recently we identified the anatomical substrates for some of the sleep changes caused by certain types of general anesthetics.We did so by using genetically modified mice in which there is endogenous expression of c-Fos, a marker of neuronal activation. However, using this new technique, we will be able to directly measure cellular excitability in groups of neurons in the brainstem that are associated with sleep. This is a major advantage over simply quantifying c-Fos expression as a surrogate marker of neuronal activation.Our next step will be to pursue the cellular and molecular mechanisms underlying the sleep changes induced by certain types of general anesthetics. This will entail measuring cellular excitability in brainstem neurons associated with sleep using neuropixel probes, as well as using spatial transcriptomic approaches to quantify and map the expression of genes related to sleep in these areas.

Silicon multielectrode-based recordings are increasingly popular for studying neuronal activity at the temporal resolution of action potentials in many ...

acute-single-unit-multi-electrode-recordings-from-brainstem-head

Without Section

Research

Acute Single-Unit Multi-Electrode Recordings from the Brainstem of Head-Fixed Mice

JoVE Journal

Neuroscience

411 vistas.  University of Virginia. Nuestro laboratorio investiga los efectos de los anestésicos de uso común en las neuronas relacionadas con el sueño y sus vías de comunicación. Nuestro objetivo es comprender mejor cómo los anestésicos afectan las vías endógenas del sueño y afectan el sueño perioperatorio y la cognición. Recientemente identificamos los sustratos anatómicos de algunos de los cambios del sueño causados por ciertos tipos de anestésicos generales.Lo hicimos ...

Video: Autor destacado: Investigación de las vías del sueño inducidas por la anestesia y la excitabilidad neuronal en ratones

Silicon multielectrode-based recordings are increasingly popular for studying neuronal activity at the temporal resolution of action potentials in many brain regions. However, recording neuronal activity from deep caudal structures like the brainstem using multi-channel probes remains challenging. A significant concern is finding a trajectory for probe insertion that avoids large blood vessels, such as the superior sagittal venous sinus and the transverse venous sinus. Injuring these large veins can cause extensive bleeding, damage to the underlying brain tissue, and potentially death. This approach describes targeting brainstem structures by coupling anterior coordinates with an angled approach, allowing the recording probe to penetrate the brain below high-risk vascular structures. Compared to a strictly vertical approach, the angled approach maximizes the number of brain regions that can be targeted. Using this strategy, the ventrolateral periaqueductal gray (vlPAG), a brainstem region associated with REM sleep, can be reproducibly and reliably accessed to obtain single-unit, multi-electrode recordings in head-fixed mice before and during sevoflurane anesthesia. The ability to record neuronal activity in the vlPAG and surrounding nuclei with high temporal resolution is a step forward in advancing the understanding of the relationship between REM sleep and anesthesia.

This protocol describes a method to obtain in vivo, high-density single-neuron recordings from the brainstem of head-fixed mice. This approach is deployed to measure the action potential firing of neurons in the ventrolateral periaqueductal gray - a brainstem region inactive during Rapid Eye Movement (REM) sleep - before and during general anesthesia.

Investigación

Neurociencias

Electrocorticography Headplate Implantation and Electrode Placement for Neuronal Activity Recording

To begin, make an electrocorticography or ECoG headset by soldering perfluoroalkoxy-coated stainless steel wire to a three-pin connector header. After identifying the insertion coordinates based on a mouse stereotaxic atlas, position the anesthetized mouse in the stereotaxic frame. Place the animal's nose in the nose cone and stabilize the head with head bars.Then perform a toe pinch test to check the depth of anesthesia. After making a five-millimeter scalp incision above the parietal and occipital bones, scrape the meninges with the scalpel blade to remove them. Use the scalpel blade to cut muscle attachments and expose the parietal and occipital bones.Apply hydrogen peroxide to control bleeding and dry the skull surface. Next, identify the bregma and lambda landmarks on the skull. Then adjust the nose cone position to level the anterior-posterior position of the skull.To level the medial lateral position of the skull, pick two opposite points between bregma and lambda and check their level. Now, measure the distance between bregma and lambda and compare it to the distance reported in the Franklin Paxinos Stereotaxic Atlas. Use the difference between the measured and reported distances to scale the anterior-posterior coordinate proportionally.Mark craniotomy coordinates on the skull with a sterilized pencil. Using a stereotaxic micro manipulator, position the headplate directly on top of the lambda suture. Apply dental cement to the headplate and around it to secure it to the skull and allow it to dry for 10 minutes.Then drill burr holes for two cortical electrodes and one reference electrode. Place the stripped ends of coated silver wire electrodes within the burr holes and secure them using ultraviolet light activated resin. Completely cover the coated stainless steel wires with dental cement so that no wire is exposed.Cover the underside and sides of the headset with dental cement to ensure it is firmly in place and allow the mouse to recover for seven days.

Electrocorticografía: Implantación de la placa de cabeza y colocación de electrodos para el registro de la actividad neuronal

Silicon Probe Placement and Single Unit Recording from the Brainstem of Head-Fixed Mice

Position the anesthetized mouse in a stereotaxic frame. Identify bregma and lambda, ensuring no more than a 100 micrometer height difference between the two landmarks. Find and mark the calculated coordinates on the skull with a sterile pencil.Around the coordinates, create an outline of the two millimeter by two millimeter craniotomy window. After checking the depth of anesthesia, use a high-speed drill to create a two millimeter by two millimeter craniotomy window. Apply 0.5 to 1 milliliter of normal saline to prevent the brain surface from drying.Remove the dura using a syringe needle and fine forceps. Next, use a high-speed drill to create a separate burr hole for the silicon probes reference electrode, generally one to two millimeters from the cranial window. Apply 0.2 milliliters of low toxicity silicon adhesive on the skull to completely seal the craniotomy.Using the head plate and screws, affix the head of the mouse to the electrophysiology recording rig. Then coat the silicon probe shank with fluorescent dye so that the probe trajectory can be reconstructed after the experiment. After that, mount the probe on the manipulator and set the desired angle.To lower the recording probe to the brain surface within the center of the cranial window, manually insert the probe to a depth of approximately 300 micrometers. Once inserted to this depth, slowly lower the probe automatically to 200 micrometers per minute to the targeted depth to minimize tissue damage. Finally, apply mineral oil to the brain surface within the craniotomy window to prevent drying.Then record data from the silicon probe and ECOG at 30 kilohertz using an Intan recording controller. Most recorded neurons decreased their firing during sevoflurane anesthesia. VLPAG firing significantly decreased from baseline to during sevoflurane.This decrease was consistent across all VLPAG neurons.