वयस्क चूहे में विशिष्ट मस्तिष्क क्षेत्रों की Excitotoxic घाव के लिए stereotaxic सर्जरी
Summary
विशिष्ट मस्तिष्क क्षेत्र की एक stereotaxic निर्देशांक का उपयोग excitotoxin की जलसेक द्वारा लक्षित पृथक (ओं) में वर्णित है. इस तकनीक को भी चूहे के मस्तिष्क में अन्य रसायनों के अर्क के लिए अनुकूलित किया जा सकता है.
Abstract
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.
Protocol
Discussion
यहाँ प्रस्तुत stereotaxic विधि के NMDA के अर्क के माध्यम से विशिष्ट मस्तिष्क क्षेत्रों की excitotoxic घाव के लिए अनुमति देता है. बुनियादी stereotaxic तरीकों के लिए एक साइट विशेष तरीके में औषधीय और जैविक एजेंटों की एक किस्म को ब…
Disclosures
The authors have nothing to disclose.
Acknowledgements
इस काम का समर्थन किया गया था फिर predoctoral फेलोशिप (EDK), NARSAD युवा अन्वेषक पुरस्कार (डी) और NIMH दिमाग (R01MH087495) पुरस्कार (डी) सीआईआरएम.
Materials
| Name of the reagent | Company | Catalogue number | Comments |
| N-Methyl-D-aspartic Acid 98% | Fisher Scientific | AC32919-0500 | |
| Dual Lab Standard Stereotaxic w/45 deg. Ear Bars | Stoelting | 51653 | Alternative vendor: Kopf *note of caution: assure compatibility of stereotaxic accessories if purchasing from multiple vendors |
| 10μl SYR SPECIAL (*/*/*) | Hamilton | 701SN | |
| Dremel Moto-Tool | Stoelting | 58600 | Alternative vendor: Kopf |
| Carbide burs, handpiece HP, size 2 | Schein Dental | 2284578 | |
| Stoelting 6 Syringe Programmable Pump | Stoelting | 53140 | Alternative vendor: Kopf |
| Stainless Steel 316 Hypodermic Regular Wall Tubing 30 Gauge .0123″ OD x .00625″ ID x .003″ Wall (infusion needle) | Small Parts | HTXX-30R-06-05 | |
| Intramedic PE 20 tubing (infusion tubing) | VWR | 63019-025 | |
| Reflex Clips, 9mm, non-sterile | Kent Scientific Corp. | INS500346 | Alternative vendor: Fine Science Tools |
| Reflex Clip Applier for 9mm clips | Kent Scientific Corp. | 12031-09 | Alternative vendor: Fine Science Tools |
| Curved Hartman hemostat | Fine Science Tools | 13003-10 | |
| London forceps | Fine Sceince Tools | 11080-02 | |
| 2% chlorhexidine solution | Allivet | 30159 | Alternative vendor: PetSolutions |
| 10% povidone iodine solution | CVS | SKU #739575 | |
| Hot bead sterilizer | Harvard Apparatus | 610183 |
Table 1. Table of specific reagents and equipment.
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