This work was supported y a CIRM predoctoral fellowship (EDK), NARSAD Young Investigator Award (DK) and the NIMH BRAINS award (R01MH087495) (DK).

Anesthesia and analgesia: Thirty minutes prior to anesthesia, inject the rat with 0.05 mg/kg subcutaneous buprenorphine for analgesia. Initiate anesthesia with 30-40 mg/kg intraperitoneal sodium pentobarbital. At this point, also inject atropine to prevent respiratory failure (0.4 mg/kg, subcutaneous) and meloxicam as further analgesic (2 mg/kg subcutaneous). If after 5 minutes, the rat is still mobile or responsive to toe pinch, give subsequent doses of sodium pentobarbital at 5 mg/kg (intraperitoneal) until the rat is ...

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The stereotaxic method presented here allows for excitotoxic lesion of specific brain areas via infusion of NMDA. The basic stereotaxic methods can be adapted to infuse a variety of pharmacological and biological agents in a site-specific manner. It can also be adapted to target a variety of brain areas, defined by their stereotaxic coordinates in a brain atlas12. Adaptation to other species such as mice can be made with similar equipment built for smaller animals. The present procedures are optimized for 3 mo...

<table border="1">
	<tbody>
		<tr>
			<td>Name of the reagent</td>
			<td>Company</td>
			<td>Catalogue number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>N-Methyl-D-aspartic Acid 98%</td>
			<td>Fisher Scientific</td>
			<td>AC32919-0500</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Dual Lab Standard Stereotaxic w/45 deg. Ear Bars</td>
			<td>Stoelting</td>
			<td>51653</td>
			<td>Alternative vendor: Kopf *note of caution: assure compatibility of stereotaxic accessories if purchasing from multiple vendors</td>
		</tr>
		<tr>
			<td>10&mu;l SYR SPECIAL (*/*/*)</td>
			<td>Hamilton</td>
			<td>701SN</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Dremel Moto-Tool</td>
			<td>Stoelting</td>
			<td>58600</td>
			<td>Alternative vendor: Kopf</td>
		</tr>
		<tr>
			<td>Carbide burs, handpiece HP, size 2</td>
			<td>Schein Dental</td>
			<td>2284578</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Stoelting 6 Syringe Programmable Pump</td>
			<td>Stoelting</td>
			<td>53140</td>
			<td>Alternative vendor: Kopf</td>
		</tr>
		<tr>
			<td>Stainless Steel 316 Hypodermic Regular Wall Tubing 30 Gauge .0123" OD x .00625" ID x .003" Wall (infusion needle)</td>
			<td>Small Parts</td>
			<td>HTXX-30R-06-05</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Intramedic PE 20 tubing (infusion tubing)</td>
			<td>VWR</td>
			<td>63019-025</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Reflex Clips, 9mm, non-sterile</td>
			<td>Kent Scientific Corp.</td>
			<td>INS500346</td>
			<td>Alternative vendor: Fine Science Tools</td>
		</tr>
		<tr>
			<td>Reflex Clip Applier for 9mm clips</td>
			<td>Kent Scientific Corp.</td>
			<td>12031-09</td>
			<td>Alternative vendor: Fine Science Tools</td>
		</tr>
		<tr>
			<td>Curved Hartman hemostat</td>
			<td>Fine Science Tools</td>
			<td>13003-10</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>London forceps</td>
			<td>Fine Sceince Tools</td>
			<td>11080-02</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>2% chlorhexidine solution</td>
			<td>Allivet</td>
			<td>30159</td>
			<td>Alternative vendor: PetSolutions</td>
		</tr>
		<tr>
			<td>10% povidone iodine solution</td>
			<td>CVS</td>
			<td>SKU #739575</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Hot bead sterilizer</td>
			<td>Harvard Apparatus</td>
			<td>610183</td>
			<td>&nbsp;</td>
		</tr>
	</tbody>
</table>
Table 1. Table of specific reagents and equipment.

stereotaxic surgery for excitotoxic lesion of specific brain areas in the adult rat

Many behavioral functions in mammals, including rodents and humans, are mediated principally by discrete brain regions. A common method for discerning the function of various brain regions for behavior or other experimental outcomes is to implement a localized ablation of function. In humans, patient populations with localized brain lesions are often studied for deficits, in hopes of revealing the underlying function of the damaged area. In rodents, one can experimentally induce lesions of specific brain regions.
Lesion can be accomplished in several ways. Electrolytic lesions can cause localized damage but will damage a variety of cell types as well as traversing fibers from other brain regions that happen to be near the lesion site. Inducible genetic techniques using cell-type specific promoters may also enable site-specific targeting. These techniques are complex and not always practical depending on the target brain area. Excitotoxic lesion using stereotaxic surgery, by contrast, is one of the most reliable and practical methods of lesioning excitatory neurons without damaging local glial cells or traversing fibers.
Here, we present a protocol for stereotaxic infusion of the excitotoxin, N-methyl-D-aspartate (NMDA), into the basolateral amygdala complex. Using anatomical indications, we apply stereotaxic coordinates to determine the location of our target brain region and lower an injection needle in place just above the target. We then infuse our excitotoxin into the brain, resulting in excitotoxic death of nearby neurons. While our experimental subject of choice is a rat, the same methods can be applied to other mammals, with the appropriate adjustments in equipment and coordinates.
This method can be used on a variety of brain regions, including the basolateral amygdala1-6, other amygdala nuclei6, 7, hippocampus8, entorhinal cortex9 and prefrontal cortex10. It can also be used to infuse biological compounds such as viral vectors1, 11. The basic stereotaxic technique could also be adapted for implantation of more permanent osmotic pumps, allowing more prolonged exposure to a compound of interest.

Watch this Scientific Journal Video about Stereotaxic Surgery for Excitotoxic Lesion of Specific Brain Areas in the Adult Rat at JoVE.com

Stereotaxic Surgery for Excitotoxic Lesion of Specific Brain Areas in the Adult Rat

Targeted ablation of specific brain region(s) by infusion of an excitotoxin using stereotaxic coordinates is described. This technique could also be adapted for infusion of other chemicals into the rat brain.

Many behavioral functions in mammals, including rodents and humans, are mediated principally by discrete brain regions. A common method for discerning the ...

stereotaxic-surgery-for-excitotoxic-lesion-specific-brain-areas-adult

Research

JoVE Journal

Neuroscience

35.0K visualizações.  University of California Berkeley. Ablação alvo de região específica do cérebro (s) por infusão de uma excitotoxina utilizando coordenadas estereotáxico é descrito. Esta técnica pode também ser adaptado para infusão de outros produtos químicos para o cérebro de rato.