Name: direct stereotaxic brain infusion of amyloid-beta proteins for an alzheimer's disease model
Uploaded: 2025-03-04T15:34:51.000+00:00
Duration: 1 min 26 s
Description: All procedures involving animal models have been reviewed by the local institutional animal care committee and the JoVE veterinary review ...

direct stereotaxic brain infusion of amyloid-beta proteins for an alzheimer's disease model

Direct Stereotaxic Brain Infusion of Amyloid-Beta Proteins for an Alzheimer's Disease Model

Make a 2- to 3-millimeter incision in the midline of the scalp with a scalpel. Use straight fine scissors to extend the incision line to about 1.0 centimeters to expose the sagittal suture, bregma, and lambda of the skull. After that, use forceps to pull the skin apart.
Clean the skull with a sterile cotton swab soaked with sterile saline. Then use a clean, dry cotton swab to dry the skull. Next, mark a dot on the bregma. Position the Hamilton syringe using the micromanipulator so that the tip of the needle just touches the dot on the bregma. Then, record the DV coordinate.
Mark a dot on the lambda point. Make sure that the AP axis of the skull is level by moving the syringe posteriorly to the lambda point. The tip of the needle should touch the lambda point as it did the bregma point. After that, record the DV position. The DV coordinates for bregma and lambda should be within 0.5 millimeters.
Now, return the needle tip to the bregma dot. Record the starting AP position. Then, calculate the ending AP position by subtracting 2 millimeters from the starting AP coordinate, and reposition the syringe needle to the final AP coordinate.
Next, record the current ML coordinate. Calculate the left and right ending ML coordinates by adding or subtracting 1.3 millimeters from the starting ML coordinate, and move the syringe needle to the ending ML coordinates. Touch the needle tip to the surface of the skull on both ending ML coordinates, and make sure the DV coordinates are within 0.5 millimeters.
While at the ending ML coordinate, pull the needle up 0.5 to 1 centimeters over the skull. Mark a dot on the skull with a dark-colored extra-fine-point marker. Repeat this step for the contralateral side of the skull. Then, move the syringe away.
Drill a hole on either the left or right ML coordinate on the skull using a 0.8-millimeter drill bit. Repeat this step for the contralateral side. Afterward, move the syringe to one of the newly introduced holes. Lower the needle to just past the skull, and be careful not to puncture the brain.
To ensure that the needle has passed the skull, gently push the needle against the skull to make sure that the needle doesn&#39;t come out of the hole. Next, record the starting DV coordinate. Calculate the ending DV coordinate by subtracting 2.2 millimeters from the starting DV coordinate, and lower the needle to the ending DV coordinate.
Then, set the stereotaxic injector pump to infuse 4 microliters of A&#946;1-42 into the dentate gyrus at a rate of 0.5 microliters per minute. After the infusion, let the needle remain in place for an additional minute to minimize backflow of solution out of the injection site. After that, move the needle to the other side of the brain and repeat the procedure.
Now, unscrew the ear bars. Use student standard pattern forceps to pull the scalp closed and seal the wound with a suture. Take off the nose guard and remove the mouse.

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Nanyang Technological University

Research

JoVE Encyclopedia of Experiments

Neuroscience

Neuropathology

Neurodegenerative Diseases

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All procedures involving animal models have been reviewed by the local institutional animal care committee and the JoVE veterinary review board.&#160;&#160;&#160;
1. Prepare Surgical Instruments and Solutions for Surgery
<ol>
	<li>Autoclave all stainless steel surgical instruments.</li>
	<li>Prepare 70% ethanol by diluting 200 proof absolute ethanol with sterile molecular grade deionized distilled water.</li>
	<li>Attach the 29 G needle to the Hamilton syringe. Clean the interior of Hamilton syringe and needle by drawing up and ejecting nanopure water repeatedly for 1 min. Repeat this procedure with 70% ethanol.
	<ol>
		<li>Remove the plunger and needle from the Hamilton syringe. Air dry the parts in a laminar flow hood O/N.</li>
		<li>Irradiate the needle and syringe with ultraviolet light for 30 min before use.</li>
	</ol>
	</li>
	<li>Prepare a saline solution by dissolving sodium chloride (NaCl) in molecular-grade water to a final weight-to-volume concentration of 0.9%. Sterilize the solution by filtering it through a 0.2 &#956;m pore filter.</li>
</ol>
2. Prepare Oligomeric amyloid-beta (A&#946;1-42)
<ol>
	<li>Monomerize and resuspend recombinant human A&#946;1-42 in dimethylsulfoxide (DMSO) to 5 mM exactly as described in the publication of Fa&#39; and others.</li>
	<li>Dilute 5 mM A&#946;1-42 with sterile (1x) phosphate-buffered saline (PBS) to 100 &#181;M on the day before surgery.</li>
	<li>Mix the solution well by trituration.</li>
	<li>Incubate A&#946;1-42 solution for 12 hr at 4&#730;C. 
	NOTE: Control solutions such as diluting DMSO in PBS or scrambled/reverse A&#946;1-42 peptide should be prepared the same way as A&#946;1-42.</li>
</ol>
3. Determine Injection Coordinates
<ol>
	<li>Use the adult mouse brain atlas to determine the exact anterior-posterior (AP), medial-lateral (ML), and dorsal-ventral (DV) coordinates for the brain region of interest. 
	&#8203;NOTE: To illustrate the technique we picked the dentate gyrus of the hippocampus as the target with the following coordinates from the bregma: AP, -2.00 mm; ML, &#177;1.3 mm; DV, -2.2 mm. The negative sign preceding the AP value indicates that it is 2.00 mm posterior of the bregma. The &#177; sign preceding the ML value indicates left and right direction from the center. Lastly, the negative sign preceding the DV indicates it is moving ventrally from the surface of the brain.</li>
</ol>
4. Stereotaxic Frame Setup
<ol>
	<li>Wear a surgical face mask, a clean lab coat, and sterile surgical gloves.</li>
	<li>Wipe down the stereotaxic instrument and mouse adaptor with 70% ethanol.</li>
	<li>Lay down a sterile surgical drape on the counter.</li>
	<li>Place the stereotaxic instrument with a mouse adaptor on top of the sterile surgical drape.</li>
	<li>Wipe the mouse heating pad with 70% ethanol. Position the heating pad over the stereotaxic frame bed. Use general-purpose laboratory labeling tape to tape down the heating pad over the mouse adaptor bed.
	<ol>
		<li>Attach the heating pad to the warm water recirculation pump according to the manufacturer&#39;s directions.</li>
		<li>Turn on the warm water recirculation pump, set the temperature to 37 &#176;C, and wait until it reaches that temperature.</li>
	</ol>
	</li>
	<li>Affix the 50 &#181;l Hamilton syringe with a 29 G needle onto the stereotaxic frame by screwing it onto the motorized vertical injecting shaft according to the manufacturer&#39;s directions.</li>
	<li>Turn on the bead sterilizer and wait until it reaches the manufacturer&#39;s preset temperature. 
	NOTE: This is used for sterilizing stainless steel instruments between animals. It takes instruments 20 sec of contact with the beads for sterilization.</li>
	<li>Turn on the hot plate, set it to 42 &#176;C, and place a clean empty cage atop.</li>
	<li>While the Hamilton syringe is fixed on the stereotaxic frame, use the motorized stereotaxic injector to draw up the A&#946;1-42 solution. 
	&#8203;NOTE: Draw up more than 4 &#956;l of the solution into the syringe and then use the stereotaxic injector to set the injecting volume. Operate the injector according to the manufacturer&#39;s instructions.</li>
</ol>
5. Animal Preparation
<ol>
	<li>Determine the weight of the mouse using the weigh scale.</li>
	<li>Anesthetize mouse with ketamine/xylazine cocktail at 100 mg/kg ketamine and 10 mg/kg xylazine by injecting intraperitoneally (IP). Monitor the depth of anesthesia by the loss of toe pinch reflex.</li>
	<li>After the mouse is sedated, take the hair clipper and shave its head to expose the skin over the skull.</li>
	<li>Place the mouse on top of the heating pad on top of the stereotaxic bed.</li>
	<li>Use the spatula to open the mouth and place the incisor teeth inside the teeth guard. Secure the nosepiece over the face of the mouse. Clamp it down gently and not too tight.</li>
	<li>Position the bilateral ear crossbars into the auditory meatus to secure the head. Move each crossbar in until it hits the skull, and then turn the screw to lock it.
	<ol>
		<li>To make sure the head is secured use your index finger to gently push down on the head. If the head is properly secured it will not give out or move when pressed.</li>
	</ol>
	</li>
	<li>Apply a drop of eye cream or an eye drop to the eyes to keep them moist. Make sure the eyes are moist throughout the surgical procedure.</li>
	<li>To disinfect the surgical site use sterile cotton swabs to apply betadine solution to the skin over the skull, followed by 70% ethanol. Perform the alternating betadine and 70% ethanol cleaning 2 more times.</li>
</ol>
6. Surgery and Infusion
<ol>
	<li>Use a scalpel to make a 2-3 mm incision in the midline of the scalp, and then use straight fine scissors to extend the incision line to 1.0-1.5 cm to expose the sagittal suture, bregma, and lambda of the skull, landmarks which the stereotaxic coordinates are based on. Use micro clamps to keep the skin apart. 
	NOTE: The bregma and lambda positions are explained in the mouse brain atlas &#34;The Mouse Brain in Stereotaxic Coordinates&#34;.</li>
	<li>Take a cotton swab, soak it in sterile saline, and use it to clean the skull. Then, use a clean dry cotton swab to dry the skull.</li>
	<li>Use a sterile fine point pen to mark a dot on the bregma. Use the stereotaxic micromanipulator to position the Hamilton syringe so that the tip of the needle just touches the dot on the bregma.
	<ol>
		<li>Record the DV coordinate.</li>
		<li>To check if the AP axis of the skull is level move the Hamilton syringe posteriorly so that the tip of the needle touches the lambda point.</li>
		<li>Record the DV position. Make sure the DV coordinates for bregma and lambda are within 0.5 mm. 
		NOTE: The goal is to minimize the DV difference between bregma and lambda.</li>
	</ol>
	</li>
	<li>Use the micromanipulator to return the Hamilton syringe needle tip back to the bregma dot.</li>
	<li>Record the starting AP position.</li>
	<li>Calculate the ending AP position by subtracting 2.00 mm from the starting AP coordinate.</li>
	<li>Use the micromanipulator to reposition the Hamilton syringe needle to the final AP coordinate.</li>
	<li>Record the current ML coordinate.</li>
	<li>Calculate the left and right ending ML coordinates by adding or subtracting 1.3 mm from the starting ML coordinate.</li>
	<li>Use the micromanipulator to move the Hamilton syringe needle to either the ending ML coordinate.
	<ol>
		<li>Touch the needle tip to the surface of the skull on both ending ML coordinates and record the DV coordinates and make sure the values are within 0.5 mm. 
		&#8203;NOTE: The goal is to minimize the DV difference between the two ending ML coordinates.</li>
		<li>While at an ending coordinate pull the needle up 0.5-1 cm over the skull. Take a sterile fine point pen to mark a dot on the surface of the skull. Repeat this step for the contralateral side of the skull.</li>
	</ol>
	</li>
	<li>Swing the Hamilton syringe clear out of the way.</li>
	<li>Attach 0.8 mm drill head to the drill. Take the drill with both hands, set elbows on the surface of the table for stability, and position the drill head slightly above the sharpie dot on either the left or right ML coordinate. Activate the drill, lower the drill tip onto the skull surface to introduce a hole in the skull. Repeat this step for the contralateral side. 
	NOTE: Some bleeding may occur from the newly introduced holes. If there is bleeding then use a clean dry cotton swab to dab the blood.</li>
	<li>Move the Hamilton syringe back into position over either of the newly introduced ML holes. Lower the Hamilton needle just past the skull. At this point be careful not to puncture the brain. To make sure the needle has passed the skull take your index finger and gently push the needle against the skull to make sure the needle doesn&#39;t exit the hole.</li>
	<li>Record the starting DV coordinate.</li>
	<li>Calculate the ending DV coordinate by subtracting 2.2 mm from the starting DV coordinate.</li>
	<li>Lower the needle down to the ending DV coordinate.</li>
	<li>Activate the stereotaxic injector pump to pump 4 &#181;l of A&#946;1-42 into the dentate gyrus at a rate of 0.5 &#181;l/min.</li>
	<li>When the infusion is complete let the needle remain in place for an additional 1 min to minimize backflow of solution out of the injection site.</li>
	<li>Move the needle to the other side of the brain and repeat steps 6.13-6.18.</li>
</ol>
7. Animal Removal and Postoperative Care
<ol>
	<li>Unscrew the ear bars and face/nose guard. Remove the mouse from the apparatus.</li>
	<li>Use a student standard pattern forceps to pull close the scalp and then seal the wound with a suture.</li>
</ol>

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Ketamine HCl (100mg/ml)</td>
			<td>Henry Schein Medical</td>
			<td>1049007</td>
			<td>100 mg ketamine per 1 kg animal</td>
		</tr>
		<tr>
			<td>Xylazine (20mg/ml)</td>
			<td>Henry Schein Medical</td>
			<td>not available</td>
			<td>10 mg xylazine per 1 kg animal</td>
		</tr>
		<tr>
			<td>A&#946;1-42</td>
			<td>David Teplow/UCLA</td>
			<td>not available</td>
			<td>100 &#956;M; This amyloid was used in the paper</td>
		</tr>
		<tr>
			<td>A&#946;1-42</td>
			<td>Bachem</td>
			<td>H-1368</td>
			<td>Can be used in place of amyloid from the Teplow lab</td>
		</tr>
		<tr>
			<td>A&#946;1-42</td>
			<td>American Peptide</td>
			<td>62-0-80B</td>
			<td>Can be used in place of amyloid from the Teplow lab</td>
		</tr>
		<tr>
			<td>Scrambled A&#946;1-42</td>
			<td>American Peptide</td>
			<td>62-0-46B</td>
			<td>Can be used as control peptide for comparing A&#946;1-42</td>
		</tr>
		<tr>
			<td>GenTeal Lubricant Eye Gel</td>
			<td>Novartis</td>
			<td>not available</td>
			<td>For keeping the mouse eyes moist during surgery; can be found in local pharmacy stores</td>
		</tr>
		<tr>
			<td>Refresh Optive Lubricant Eye Drops</td>
			<td>Allergan</td>
			<td>not available</td>
			<td>For keeping the mouse eyes moist during surgery; can be found in local pharmacy stores; Can be used in place of GenTeal</td>
		</tr>
		<tr>
			<td>Betadine</td>
			<td>Stoelting</td>
			<td>50998</td>
			<td>For sanitizing and disinfecting</td>
		</tr>
		<tr>
			<td>Round/Tapered Spatula</td>
			<td>VWR</td>
			<td>82027-490</td>
			<td>For opening animal mouth</td>
		</tr>
		<tr>
			<td>Bulldog Serrefines Clamps (Jaw Dims. 9X1.6mm; Length 28mm)</td>
			<td>Fine Science Tools</td>
			<td>18050-28</td>
			<td>Optional; For keeping scalp skin apart during injection</td>
		</tr>
		<tr>
			<td>Straight Fine Scissors (Cutting edge 25mm; Length 11.5cm)</td>
			<td>Fine Science Tools</td>
			<td>14060-11</td>
			<td>For cutting scalp</td>
		</tr>
		<tr>
			<td>#3 Scalpel Handle</td>
			<td>Fine Science Tools</td>
			<td>10003-12</td>
			<td></td>
		</tr>
		<tr>
			<td>#11 Surgical Blade</td>
			<td>Fine Science Tools</td>
			<td>10011-00</td>
			<td>For making scalp incision</td>
		</tr>
		<tr>
			<td>Student Standard Pattern Forcep (Tip Dims. 2.5x1.5mm; Length 11.5cm)</td>
			<td>Fine Science Tools</td>
			<td>91100-12</td>
			<td>For holding scalp closed during suturing</td>
		</tr>
		<tr>
			<td>Trimmer Combo Kit</td>
			<td>Kent Scientific</td>
			<td>CL9990-1201</td>
			<td>For shaving hair</td>
		</tr>
		<tr>
			<td>T/Pump Warm Water Recirculator</td>
			<td>Kent Scientific</td>
			<td>TP-700</td>
			<td>For warming animal during surgery</td>
		</tr>
		<tr>
			<td>Resusable Warmining Pad (5&#34; x 10&#34;)</td>
			<td>Kent Scientific</td>
			<td>TPZ-0510FEA</td>
			<td>For attaching it to the T/Pump warm water recirculator to warm the animal during surgery</td>
		</tr>
		<tr>
			<td>Cordless Micro Drill</td>
			<td>Stoelting</td>
			<td>58610</td>
			<td>Use 0.8mm steel burrs to drill holes in the skull</td>
		</tr>
		<tr>
			<td>Lab Standard Stereotaxic Instrument with Mouse &#38; Neonatal Rat Adaptor</td>
			<td>Stoelting</td>
			<td>51615</td>
			<td></td>
		</tr>
		<tr>
			<td>Just for Mouse Stereotaxic Instrument</td>
			<td>Stoelting</td>
			<td>51730</td>
			<td>Can use this in place of Stoelting Cat. #51615</td>
		</tr>
		<tr>
			<td>Quintessential Stereotaxic Injector</td>
			<td>Stoelting</td>
			<td>53311</td>
			<td></td>
		</tr>
		<tr>
			<td>Dry Glass Bead Sterilizer</td>
			<td>Stoelting</td>
			<td>50287</td>
			<td>For sterilizing stainless steel instruments</td>
		</tr>
		<tr>
			<td>Sterile Surgical Drape (18&#34; x 26&#34;)</td>
			<td>Stoelting</td>
			<td>50981</td>
			<td></td>
		</tr>
		<tr>
			<td>Hamilton Syringe 50 ml, Model 705 RN SYR, NDL</td>
			<td>Hamilton Company</td>
			<td>7637-01</td>
			<td>For brain injection; use different syringes for different solutions</td>
		</tr>
		<tr>
			<td>29 Gauge Needle, Small Hub RN NDL</td>
			<td>Hamilton Company</td>
			<td>7803-06</td>
			<td>For attaching to the Hamilton syringe for brain injection</td>
		</tr>
		<tr>
			<td>1 ml BD Tuberculin Syringes</td>
			<td>VWR</td>
			<td>BD309659</td>
			<td>For administering anesthesia and saline</td>
		</tr>
		<tr>
			<td>30 Gauge Needle (0.5&#34;)</td>
			<td>VWR</td>
			<td>BD305106</td>
			<td>For administering anesthesia and saline</td>
		</tr>
		<tr>
			<td>Portable Electronic CS Series Scale (Ohaus)</td>
			<td>VWR</td>
			<td>65500-202</td>
			<td>For weighing animals to determine anesthesia dose</td>
		</tr>
		<tr>
			<td>Hot plate (Top Plate Dims. 7.25x7.25 in)</td>
			<td>VWR</td>
			<td>47751-148</td>
			<td>For warming animals post-surgery</td>
		</tr>
		<tr>
			<td>Sofsilk Silk Suture C-1 Cutting 3/8, 12 mm</td>
			<td>Covidien</td>
			<td>S1173</td>
			<td>For closing wound</td>
		</tr>
		<tr>
			<td>Vetbond Tissue Adhesive (3M)</td>
			<td>Santa Cruz Biotechnology</td>
			<td>sc-361931</td>
			<td>Optional: for aiding in wound closure; Use with suture.</td>
		</tr>
		<tr>
			<td>Cotton-Tipped Wooden-Shaft Sterile Applicators</td>
			<td>Fisher scientific</td>
			<td>22-029-488</td>
			<td>For cleaning and drying surgical wound</td>
		</tr>
		<tr>
			<td>Fisherbrand Superfrost Plus Microscope Slides</td>
			<td>Fisher Scientific</td>
			<td>12-550-15</td>
			<td>For collecting brain sections</td>
		</tr>
		<tr>
			<td>VWR Micro Cover Glass 24 X 50 mm</td>
			<td>VWR</td>
			<td>48393241</td>
			<td>For mounting microscope slides</td>
		</tr>
		<tr>
			<td>Thermo Scientific Nalgene Syringe Filter 0.2 &#956;m</td>
			<td>Fisher Scientific</td>
			<td>194-2520</td>
			<td>For sterilizing saline solution</td>
		</tr>
		<tr>
			<td>Sterile dual tip skin markers by Viscot Medical</td>
			<td>Medline</td>
			<td>VIS1422SRL91</td>
			<td>For marking coordinates on the skull</td>
		</tr>
	</tbody>
</table>

Source: Jean, Y. Y. et al., <a href="https://app-jove-com.remotexs.ntu.edu.sg/v/52805">Stereotaxic Infusion of Oligomeric Amyloid-beta into the Mouse Hippocampus.</a> J. Vis. Exp. (2015)
This video demonstrates the precise stereotaxic infusion of amyloid beta into the dentate gyrus to establish a mouse model of Alzheimer&#39;s disease. Accurate coordinate determination and controlled delivery of amyloid beta proteins result in neuronal degradation, disrupting memory processing and contributing to Alzheimer&#39;s disease development.

All procedures involving animal models have been reviewed by the local institutional animal care committee and the JoVE veterinary review ...

Begin with an anesthetized mouse with an exposed skull. The mouse is secured in a stereotaxic frame containing a syringe pre-filled with aggregation-prone amyloid-beta proteins.
Mark the bregma, a key reference point for determining protein infusion coordinates.
Move the syringe, and touch the bregma, then the lambda, to determine the dorsal-ventral coordinates, ensuring precise needle depth.
Reposition the syringe above the predetermined medial-lateral coordinate, targeting the dentate gyrus, crucial for memory processing.
Touch the skull surface, ensuring the dorsal-ventral coordinate is within the limit, and mark it. Repeat this procedure on the opposite side.
Drill at the marked medial-lateral coordinate, inject the amyloid-beta proteins into the dentate gyrus, and hold to prevent backflow.
Drill and inject amyloid-beta proteins on the opposite side for uniform protein dispersion.
Detach the ear bars from the mouse, then suture the incision.
Over time, amyloid-beta proteins aggregate to form plaques that degrade dentate gyrus neurons and disrupt memory processing, resulting in Alzheimer&#39;s disease.

19 조회수. 알츠하이머병 모델을 위한 아밀로이드-베타 단백질의 직접 입체성 뇌 주입

비디오: 알츠하이머병 모델을 위한 아밀로이드-베타 단백질의 직접 입체성 뇌 주입 - 실험

Mouse Microsurgery Infusion Technique for Targeted Substance Delivery into the CNS via the Internal Carotid Artery

Animal models of central nervous system (CNS) diseases and, consequently, blood-brain barrier disruption diseases, require the delivery of exogenous substances into the brain. These exogenous substances may induce injurious impact or constitute therapeutic strategy. The most common delivery methods of exogenous substances into the brain are based on systemic deliveries, such as subcutaneous or intravenous routes. Although commonly used, these approaches have several limitations, including low delivery efficacy into the brain. In contrast, surgical methods that locally deliver substances into the CNS are more specific and prevent the uptake of the exogenous substances by other organs. Several surgical methods for CNS delivery are available; however, they tend to be very traumatic. Here, we describe a mouse infusion microsurgery technique, which effectively delivers substances into the brain via the internal carotid artery, with minimal trauma and no interference with normal CNS functionality.

Mouse Microsurgery Infusion Technique for Targeted Substance Delivery into the CNS via the Internal Carotid Artery

The present protocol describes a mouse microsurgery infusion technique, which effectively delivers substances directly into the brain via the internal carotid artery.

중추 신경계에 대상 물질 전달을위한 마우스 미세 주입 기술<i&gt;를 통해</i&gt; 내부 경동맥

Animal models of central nervous system (CNS) diseases and, consequently, blood-brain barrier disruption diseases, require the delivery of exogenous ...

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Visualizing Axonal Growth Cone Collapse and Early Amyloid &#946; Effects in Cultured Mouse Neurons

Amyloid-&#946; (A&#946;) causes memory impairments in Alzheimer's disease (AD). Although therapeutics have been shown to reduce A&#946; levels in the brains of AD patients, these do not improve memory functions. Since A&#946; aggregates in the brain before the appearance of memory impairments, targeting A&#946; may be inefficient for treating AD patients who already exhibit memory deficits. Therefore, downstream signaling due to A&#946; deposition should be blocked before AD development. A&#946; induces axonal degeneration, leading to the disruption of neuronal networks and memory impairments. Although there are many studies on the mechanisms of A&#946; toxicity, the source of A&#946; toxicity remains unknown. To help identify the source, we propose a novel protocol that uses microscopy, gene transfection, and live cell imaging to investigate early changes caused by A&#946; in axonal growth cones of cultured neurons. This protocol revealed that A&#946; induced clathrin-mediated endocytosis in axonal growth cones followed by growth cone collapse, demonstrating that inhibition of endocytosis prevents A&#946; toxicity. This protocol will be useful in studying the early effects of A&#946; and may lead to more efficient and preventative AD treatment.

Here a protocol to investigate the early effects of amyloid-&#946; (A&#946;) in the brain is presented. This shows that A&#946; induces clathrin-mediated endocytosis and collapse of axonal growth cones. The protocol is useful in studying early effects of A&#946; on axonal growth cones and may facilitate prevention of Alzheimer's disease.

시각화 Axonal 성장 콘 붕괴 교양된 마우스 신경에 있는 초기 아 밀 로이드 β 효과

Amyloid-&#946; (A&#946;) causes memory impairments in Alzheimer's disease (AD). Although therapeutics have been shown to reduce A&#946; levels in the ...

Full- versus Sub-Regional Quantification of Amyloid-Beta Load on Mouse Brain Sections

Extracellular accumulation of amyloid-beta (A&#946;) plaques is one of the major pathological hallmarks of Alzheimer's disease (AD), and is the target of the only FDA-approved disease-modifying treatment for AD. Accordingly, the use of transgenic mouse models that overexpress the amyloid precursor protein and thereby accumulate cerebral A&#946; plaques are widely used to model human AD in mice. Therefore, immunoassays, including enzyme-linked immunosorbent assay (ELISA) and immunostaining, commonly measure the A&#946; load in brain tissues derived from AD transgenic mice. Though the methods for A&#946; detection and quantification have been well established and documented, the impact of the size of the region of interest selected in the brain tissue on A&#946; load measurements following immunostaining has not been reported. Therefore, the current protocol aimed to compare the A&#946; load measurements across the full- and sub-regions of interest using an image analysis software. The steps involved in brain tissue preparation, free-floating brain section immunostaining, imaging, and quantification of A&#946; load in full- versus sub-regions of interest are described using brain sections derived from 13-month-old APP/PS1 double transgenic male mice. The current protocol and the results provide valuable information about the impact of the size of the region of interest on A&#946;-positive area quantification, and show a strong correlation between the A&#946;-positive area obtained using the full- and sub-regions of interest analyses for brain sections derived from 13-month-old male APP/PS1 mice that show widespread A&#946; deposition.

The present protocol describes and compares the procedure to perform a full-region or sub-region of interest analysis of sagittal mouse brain sections to quantify amyloid-beta load in the APP/PS1 transgenic mouse model of Alzheimer's disease.

마우스 뇌 절편에 대한 아밀로이드-베타 부하의 전체 대 하위 지역 정량화

Extracellular accumulation of amyloid-beta (A&#946;) plaques is one of the major pathological hallmarks of Alzheimer's disease (AD), and is the target of ...

Direct Stereotaxic Brain Infusion of Amyloid-Beta Proteins for an Alzheimer's Disease Model

내레이션 대본

Direct Stereotaxic Brain Infusion of Amyloid-Beta Proteins for an Alzheimer's Disease Model